WASHINGTON -- The CIA has been delivering light machine guns and other small arms to Syrian rebels for several weeks, following President Barack Obama's decision to arm the rebels.

The agency has also arranged for the Syrian opposition to receive anti-tank weaponry like rocket-propelled grenades through a third party, presumably one of the Gulf countries that has been arming the rebels, a senior U.S. intelligence official and two former intelligence officials said Thursday. They spoke on condition of anonymity because they were not authorized to discuss the classified program publicly.

The Washington Post and The Wall Street Journal first reported the lethal aid.

Top rebel commander Gen. Salim Idris told NPR on Thursday that rebels had received no such aid from the U.S. The CIA declined to comment.

The officials said the aid has been arriving for more than a month, much of it delivered through a third party, which could explain why the rebel commander Idris does not believe the U.S. directly delivered the aid. The officials said the aid is delivered to commanders who have been vetted by the CIA, and the path of the weaponry is tracked through trusted parties within the country – though eventually, once they're in the hands of fighters, the U.S. loses sight of where the weapons go.

The rebels continue to request sophisticated anti-aircraft weaponry to take out the Syrian regime's helicopters, but the officials said neither the U.S. nor Syria's neighboring countries, like Jordan or Israel, wants the rebels to have weaponry that may fall into the hands of the al-Qaida-linked rebel group al-Nusra, or captured by Hezbollah fighters who are bolstering the Syrian army's effort.

The CIA program is classified as covert, which means it would be briefed to Congress's intelligence committees but not its defense committees. That explains why some senior lawmakers on the defense committees have complained the lethal aid was not arriving, two of the officials said.

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  • Susan Rice

    "All of this is horrific. All of us as human beings feel terrible when we see the extraordinary loss of life that [has] occurred in Syria," Rice said. "With chemical weapons, they can kill with indiscriminate abandon. People who are innocent are employed in conflict. It is of a greater magnitude because if terrorists get ahold of those weapons, if other dictators get ahold of those weapons, they can be used on a massive scale."

  • John Boehner

    "We have enemies around the world that need to understand that we're not going to tolerate this type of behavior."

  • John McCain

    "I am against delaying reaction to what is a massacre of a thousand people," McCain said. "You saw these pictures of these dead children. Come on. This is horrific. We can't stand by and watch this happen."

  • John Kerry

    "This is what Assad did to his own people," Kerry said. If the U.S. allowed "a thug and a murderer like Bashar al-Assad" to get away with gassing his own people, he added, "there will be no end to the test of our resolve and the dangers that will flow from those others who believe that they can do as they will."

  • Rand Paul

    "I think the Islamic rebels winning is a bad idea for the Christians, and all of a sudden we'll have another Islamic state where Christians are persecuted," Paul said.

  • Sarah Palin

    "As I said before, if we are dangerously uncertain of the outcome and are led into war by a Commander-in-chief who can’t recognize that this conflict is pitting Islamic extremists against an authoritarian regime with both sides shouting 'Allah Akbar' at each other, then let Allah sort it out," Palin continued.

  • Ted Cruz

    “We should be focused on defending the United States of America. That’s why young men and women sign up to join the military, not to, as you know, serve as Al Qaeda’s air force.”

  • Barack Obama

    "This attack is an assault on human dignity. It also presents a serious danger to our national security. It risks making a mockery of the global prohibition on the use of chemical weapons. It endangers our friends and our partners along Syria’s borders, including Israel, Jordan, Turkey, Lebanon and Iraq. It could lead to escalating use of chemical weapons, or their proliferation to terrorist groups who would do our people harm. "In a world with many dangers, this menace must be confronted."

  • Bob Menendez

    "Assad has made a calculation now ... that he can use chemical weapons, or he believes he can use chemical weapons without consequence," Menendez said. "And in doing so there is a global message that in fact other state actors and other non-state actors may believe they can do so as well."