AMMAN, Jordan — A car bomb ripped through Syria's largest city of Aleppo on Sunday, killing at least 17 people and wounding 40 in one of the main battlegrounds of the country's civil war, state-run media said.

Al-Qaida-style bombings have become increasingly common in Syria, and Western officials say there is little doubt that Islamist extremists, some associated with the terror network, have made inroads in the country as instability has spread. But the main fighting force looking to oust President Bashar Assad is the Free Syrian Army, a group made up largely of defected Syrian soldiers.

Sunday's blast came hours after a Jordanian militant leader linked to al-Qaida warned that his extremist group will launch "deadly attacks" to help the rebels in Syria topple Assad.

In a speech delivered to a crowd of nearly 200 followers protesting outside the prime minister's office in Amman, Mohammad al-Shalabi, better known as Abu Sayyaf, told Assad that "our fighters are coming to get you."

The warning fueled concern that Syria's civil war is providing a new forum for foreign jihadists, who fought alongside Iraqi Sunni insurgents after the 2003 invasion of Iraq and are sending fighters to help the Taliban in Afghanistan.

A Jordan-based Western diplomat who monitors Syria from his base in Jordan said the number of foreign fighters is about 100 but that figure is gradually rising. He spoke on condition of anonymity, saying identifying him further could risk his ability to gather information on Syria.

"From this podium, we declare jihad (holy war) against the wicked Assad, who is shedding the blood of our Sunni Muslim brothers in Syria," Abu Sayyaf yelled through a loudspeaker.

Abu Sayyaf is the head of Jordan's Salafi Jihadi group, which was blamed for the 2002 assassination of U.S. aid worker Laurence Foley outside his Amman home. He himself was convicted in 2004 of plotting attacks on Jordanian air bases hosting American trainers but served his term and was released last year.

The fight for Aleppo, a city of 3 million that was once a bastion of support for President Bashar Assad, is critical for both the regime and the opposition. Its fall would give the opposition a major strategic victory with a stronghold in the north near the Turkish border. A rebel defeat, at the very least, would buy Assad more time.

State-run TV aired footage of fire trucks trying to extinguish the blaze and rescue workers digging through mounds of rubble left by the car bomb. Aleppo's governor, Mohammed Wahid Akkad, was quoted by Syria's official news agency, SANA, as saying 17 dead were civilians.

No group immediately claimed responsibility for the attack. SANA blamed terrorists, the term the regime uses for rebels. Opposition activists could not immediately be reached for comment.

Fighting also raged elsewhere in Syria, with at least 58 people reported killed and scores wounded, according to the Syrian Observatory for Human Rights – a Britain-based monitoring group. That figure excluded the car bomb but included eight killed in an air raid earlier in Aleppo that flattened a residential building, the group said.

The Free Syrian Army said the strikes came hours after rebels overran army barracks in the Hananu neighborhood.

The Syrian conflict has its roots in mostly peaceful street protests that started in March last year. Since then, it has expanded into a civil war, with 23,000 people killed so far, according to human rights activists.

Most rebel leaders deny outright that foreigners are among their ranks. Others say foreigners have only a limited presence.

Still, as the battle grinds on, observers have noticed increasingly sectarian overtones to some of the violence, suggesting any power vacuum will usher in a bloodbath pitting Syria's majority Sunni population against the Assad family's minority Alawite sect, which is an offshoot of Shiite Islam.

Syria's rebels enjoy widespread sympathy across Sunni Arab countries.

On the diplomatic front, Syrian Foreign Ministry spokesman Jihad Makdessi criticized France, saying its growing support for the opposition does nothing but hinder the mission of the new U.N.-Arab League envoy, Lakhdar Brahimi, who is tasked with brokering a diplomatic solution to the conflict.

France, Syria's one-time colonial ruler, has been one of the most outspoken Western critics of the Assad regime and announced earlier this month that it has begun sending direct aid and money to five rebel-held Syrian cities as part of intensified efforts to weaken Assad. It was the first such move by a Western power.

Makdessi said France suffers from "schizophrenia" in its approach to the country's conflict.

"On the one hand, it supports Brahimi's mission, while at the same time it makes statements demonstrating that it supports the militarization of the crisis in Syria," Makdessi told The Associated Press.

French officials have acknowledged providing communications and other non-lethal equipment to Syrian rebel forces, but say they won't provide weapons without international agreement. France played a leading role in the international campaign against Libya's dictator Moammar Gadhafi last year.

Diplomatic efforts to solve the seemingly intractable conflict have failed so far. A peace plan by former U.N. Secretary-General Kofi Annan never got off the ground, and Annan quit his post as special U.N. envoy. He was replaced Sept. 1 by Brahimi, a 78-year-old former Algerian foreign minister.

Makdessi reaffirmed that Syria is "fully committed to cooperating with Brahimi," adding that "the only way to make Brahimi's mission a success is the cooperation of all parties to enable him to bring about calmness and then the political process."

In Iran, a Foreign Ministry official said that Brahimi would visit Iran as part of efforts to revive a peace effort, according to the semiofficial Mehr news agency. It quoted Deputy Foreign Minister Abbas Eraghchi as saying Brahimi will visit Tehran at an "appropriate time" but gave no other details.

The Assad regime made similar public statements of cooperation when it signed on to Annan's peace plan, only to frequently ignore or outright violate its commitments by refusing to pull troops out of cities and cease its shelling of opposition areas.

Back in Syria, activists also reported clashes between government forces and rebels in a Palestinian refugee camp on the outskirts of the capital, Damascus, in the central city of Homs, in the northern city of Idlib, in the eastern city of Deir el-Zour and the restive southern town of Daraa bordering Jordan.

The Observatory said the heaviest fighting was in Homs, where 17 people had been killed.

___

Aji reported from Damascus, Syria.

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  • March 2011

    Protests erupt in the Southern city of Daraa after 15 young boys were arrested for spraying anti-government slogans on a city wall.

  • April 19, 2011

    In an attempt to ease the protests, the Syrian government passes a bill that lifts Syria's 48-year emergency rule. <br> <em>In this citizen journalism image made on a mobile phone and acquired by the AP, taken Monday April 18, 2011, Syrians pray in Clock Square in the center of the city of Homs, Syria. (AP)</em>

  • April 22, 2011

    Security forces and gunmen loyal to President Bashar al-Assad kill at least 100 protesters, rights group said. <br> <em>Syrian anti-government protesters gesture as they demonstrate following Friday prayers in the central city of Homs, Syria, Friday, April 22, 2011. (AP)</em>

  • May 23, 2011

    The European Union imposed sanctions on president Bashar Assad and nine other senior government officials.<br> <em>Syrian President Bashar Assad, seen, during a meeting with his Iranian counterpart Mahmoud Ahmadinejad, unseen, at the presidency in Tehran, Iran, Wednesday, Aug. 19, 2009. (AP)</em>

  • November 12, 2011

    The Arab League suspends Syria.<br> <em>General view of the Arab League emergency session on Syria at the Arab League headquarters in Cairo, Egypt, Saturday, Nov.12, 2011. (AP)</em>

  • December 7, 2011

    Assad denies ordering his troops to kill peaceful demonstrators, telling U.S. television channel ABC that only a "crazy" leader kills his own people.<br> <em>In this image from amateur video made available by the Ugarit News group on Wednesday, Dec. 7, 2011, the coffins of three protesters are carried during a march in Homs, Syria. (AP)</em>

  • December 27, 2011

    Arab League monitors said they saw "nothing frightening" during an initial visit to Homs, as 20,000 people held protests there. The monitor mission was part of an Arab League peace plan negotiated between the organization and the Assad regime to end the bloodshed in the country.<br> <em>In this image made from amateur video released by Shaam News Network and dated Wednesday Dec. 28, 2011, purports to show Arab League monitors visiting the Baba Amr area of Homs in Syria. (AP)</em>

  • January 28, 2012

    The Arab League suspends its monitoring mission while violence becomes increasingly gruesome.<br> <em>This citizen journalism image provided by the Local Coordination Committees in Syria and released on Friday Jan. 27, 2012, purports to show the bodies of five Syrian children wrapped in plastic bags, with signs in Arabic identifying them by name. (AP)</em>

  • January 31, 2012

    Government forces reasserted control over parts of Damascus as Syrian rebels withdrew, after three days of fighting that activists say killed at least 100 people.<br> <em>Syrian rebels hold their RPG and their guns as they stand on alert during a battle with the Syrian government forces, at Rastan area in Homs province, central Syria, on Tuesday Jan. 31, 2012. (AP)</em>

  • February 4, 2012

    Russia and China vetoed a resolution from the U.N. Security Council calling for Assad to step down.<br> <em>An anti-Syrian regime protester holds up a placard against Russia as others chant slogans during a midnight demonstration against Syrian President Bashar Assad, in the suburb of Kedssaya, in Damascus, Syria, on Saturday Feb. 4, 2012. (AP)</em>

  • February 16, 2012

    The U.N. General Assembly approved a resolution endorsing the Arab League plan calling for Assad to step aside.<br> <em>In this citizen journalism image provide by the Local Coordination Committees in Syria, anti-Syrian regime protesters hold an Arabic banner which reads "Homs is the city of the orphan Syrian revolution," as they march during a demonstration against Syrian President Bashar Assad, at Dael village in Daraa province, south Syria, on Friday, Feb. 17, 2012. (AP)</em>

  • February 22, 2012

    More than 80 people were killed in Homs including two foreign journalists, Marie Colvin and Remi Ochlik. Syrian security forces shelled Homs for nearly a month in an attempt to drive Syrian Free Army fighters out. Activists say hundreds of people have died in the siege. <br> <em>This is an undated image of journalist Marie Colvin, made available Wednesday, Feb. 22, 2012 by the Sunday Times in London. (AP)</em>

  • February 23, 2012

    Former U.N. Secretary-General Kofi Annan was appointed U.N.-Arab League envoy to Syria. <br>

  • February 27, 2012

    Opposition fighters leave the besieged neighborhood of Baba Amr in Homs. Government troops vow to 'cleanse' the neighborhood. <i>In this Tuesday, Feb. 21, 2012 citizen journalism image provided by the Local Coordination Committees in Syria and accessed on Wednesday, Feb. 22, 2012, black smoke rises into the air from Syrian government shelling, at Baba Amr neighborhood in Homs province, Syria. (AP Photo/Local Coordination Committees in Syria)</i>

  • February 28, 2012

    According to Assad, 90 percent of voters endorsed a new constitution in a referendum on February 26. The declaration was widely dismissed as a sham.<br>

  • March 8, 2012

    Syria's deputy oil minister announces his defection in a YouTube video.

  • March 14, 2012

    The Guardian obtains thousands of emails that appear to have been sent and received by Syrian president Bashar Assad and his wife Asma. <i>In this photo released by the Syrian official news agency SANA, Syrian President Bashar Assad casts his ballot next to his wife Asma at a polling station during a referendum on the new constitution, in Damascus, Syria, on Sunday Feb. 26, 2012. (AP Photo/SANA)</i>

  • March 15, 2012

    The U.N. estimates 8,000 people have been killed in the conflict. <i>In this March 9, 2012 citizen journalism image provided by the Homs City Union of The Syrian Revolution, smoke rise from a building that was shelled by the Syrian army, at Jeb al-Jandali neighborhood in Homs province, central Syria. (AP Photo/Homs City Union of The Syrian Revolution)</i>

  • March 25, 2012

    The UN raises the estimated death toll in Syria's conflict to 9,000. <i> This image made from amateur video and released by Shaam News Network Saturday, March 24, 2012, purports to show smoke rising after rockets fell in the Khaldiyeh area of Homs, Syria. (AP Photo/Shaam News Network via AP video) </i>

  • March 27, 2012

    Syria accepts a six-point peace plan offered by U.N.-Arab League envoy Kofi Annan.

  • April 9, 2012

    Syrian forces fire into a refugee camp across the Turkish border. <i>In this Monday, April 9, 2012 photo, Syrian refugees are seen in camp in Reyhanli, Turkey. (AP Photo/Germano Assad) </i>

  • April 12, 2012

    A U.N.-brokered ceasefire takes hold. Regime forces stop assaults, but fail to retreat from city centers. <i>Pro-Syrian government demonstrators hold a rally at Sabe Bahrat Square to commemorate the 65th anniversary of the foundation of the Ruling Baath Arab Socialist Party in Damascus, Syria, Saturday, April 7, 2012. (AP Photo Bassem Tellawi) </i>

  • April 14, 2012

    The U.N. Security Council approves a resolution to send observers to Syria to monitor the implementation of the ceasefire.

  • April 21, 2012

    The UN sends 300 observers to Syria for three months to monitor the "ceasefire." <em>In this photo released by the Syrian official news agency SANA, a UN observer and Syrian army officer, left, listen to Syrian citizens during their visit to the pro-Syrian regime neighborhoods, in Homs province, central Syria, on Monday April 23, 2012. (AP Photo/SANA)</em>

  • April 25, 2012

    A rocket attack on the city Hama kills 69, including some children. <em>In this image made from amateur video released by the Ugarit News and accessed Wednesday, April 25, 2012, purports to show Syrians standing in rubble of damaged buildings from Syrian forces shelling in Hama, Syria. (AP Photo/Ugarit News via AP video) </em>

  • April 27, 2012

    An explosion in the Midan neighborhood of Damascus, Syria kills 11 and injures 28. <em>Syrian investigators, right, gather next to a damaged police bus that was attacked by an explosion in the Midan neighborhood of Damascus, Syria, on Friday April 27, 2012. (AP Photo/Bassem Tellawi)</em>

  • May 7, 2012

    Parliamentary elections are held. While the regime sees the elections as an indication of its willingness to concede to democratic reforms, the opposition dismisses the elections as a sham. <em>In this photo taken during a government-organized tour, Syrian campaign workers wait outside a polling station during the parliamentary elections, in Damascus, Syria, Monday, May 7, 2012. (AP Photo/Muzaffar Salman)</em>

  • May 10, 2012

    Two explosions near a military intelligence complex in Damascus killed 55. <em>Syrian inspectors investigate the crater in front of a damaged military intelligence building where two bombs exploded, at Qazaz neighborhood in Damascus, Syria, on Thursday May 10, 2012. (AP Photo/Bassem Tellawi)</em>

  • May 25, 2012

    A massacre occurs in the village of Houla, where 108 people were killed. Activists blamed the regime for the massacre, although the Syrian government denies all responsibility. <em>This frame grab made from an amateur video provided by Syrian activists on Monday, May 28, 2012, purports to show the massacre in Houla on May 25 that killed more than 100 people, many of them children. (AP Photo/Amateur Video via AP video)</em>

  • More explosions in Hama kill scores more. <em>In this citizen journalism image provided by Sham News Network SNN and according to them, purports to show the bodies of Syrian children in Mazraat al-Qubair on the outskirts of Hama, central Syria, Thursday, June 7, 2012. (AP Photo/Shaam News Network, SNN)</em>

  • June 12, 2012

    The head of the UN peacekeeping operations, Herve Ladsous, calls the Syria crisis a "civil war." <em>A Nepalese human rights activist holds a placard against the human rights violation in Syria as they take part in a protest organized by the Amnesty International outside the United Nations office in Katmandu, Nepal, Wednesday, June 13, 2012. (AP Photo/Niranjan Shrestha)</em>

  • June 22, 2012

    Syria shoots down Turkish warplane, for which Syrian President Bashar Assad expressed regret. <em>In this April 29, 2010 file photo, a Turkish pilot salutes before take-off at an air base in Konya, Turkey. (AP Photo/File)</em>

  • June 26, 2012

    Assad announces that his country is in a state of war. <em>In this image taken from TV Syria's president Bashar al-Assad speaks during an interview in Tehran, Iran, Thursday June 28, 2012. (AP Photo/IRIB TV via APTN) </em>

  • July 6, 2012

    General Manaf Tlas, son of Mustafa Tlas and a member of Assad's inner circle, defects and flees to France. <em>In this Feb. 22, 1971 file photo, Army Chief of Staff Gen. Mustafa Tlas (front row, 2nd from right) and Air Force General Naji Jamil (1st right) surrounded by other members of Parliament on election day in Damascus, Syria. (AP Photo, File)</em>

  • July 11, 2012

    Nawaf al-Fares, Assad's ambassador to Iraq, defects and joins the Syrian opposition. <em>In this Sept. 16, 2008 file photo provided by the Syrian official news agency SANA, Nawaf Fares, left, is sworn in as Syria's ambassador to Iraq before Syrian President Bashar Assad, right, and Syrian Foreign Minister Walid Moallem in Damascus. (AP Photo/SANA, File)</em>

  • July 12, 2012

    Up to 200 people, most of them civilians, are killed in the village of Tremseh. The massacre is condemned by the international community. <em>In this citizen journalism image provided by Shaam News Network SNN, taken on Saturday, July 14, 2012, a woman holds a child in front of their destroyed home in Tremseh, Syria about 15 kilometers (9 miles) northwest of the central city of Hama. (AP Photo/Shaam News Network, SNN)</em>

  • July 18, 2012

    Former Defense Minister Hassan Turkmani, Syrian Defense Minister Gen. Dawoud Rajha, and Bashar Assad's brother-in-law Major General Assef Shawkat are killed in a bomb attack on Damascus. <em>This undated combo image made of 3 photos released by the Syrian official news agency SANA, shows former defense minister Hassan Turkmani, left, Syrian Defense Minister Gen. Dawoud Rajha, center, and Bashar Assad's brother-in-law Major General Assef Shawkat, right, in Damascus, Syria. (AP Photo/SANA)</em>

  • July 12, 2012

    Activists say more than a hundred people were killed in the village of Tremseh, near the city of Hama. <em>In this citizen journalism image provided by Shaam News Network SNN, taken on Saturday, July 14, 2012, a woman holds a child in front of their destroyed home in Tremseh, Syria about 15 kilometers (9 miles) northwest of the central city of Hama. (AP Photo/Shaam News Network, SNN)</em>

  • August 6, 2012

    Syria's prime minister Riyad Hijab defects and flees to Jordan. <em>Riad Hijab, Syria┬'s defected former prime minister, speaks at a press conference at the Hyatt Hotel in Amman, Jordan, Tuesday, Aug. 14, 2012. (AP photo/Mohammad Hannon)</em>