* More than 280 confirmed dead, toll set to rise
* Protests in several cities as unions call for action
* PM Erdogan's reaction sparks further anger
* Mining community holds mass burials (Adds comment from Erdogan aide, updates toll)
By Ece Toksabay
SOMA, Turkey, May 15 (Reuters) - Loudspeakers broadcast the names of the dead as rows of graves were filled in this close-knit Turkish mining town on Thursday, while thousands protested in major cities as grief turned to anger following the country's deadliest industrial disaster.
Rescuers were still trying to reach parts of the coal mine in Soma, 480 km (300 miles) southwest of Istanbul, more than 48 hours after fire knocked out power and shut down the ventilation shafts and elevators, trapping hundreds underground.
At least 283 people have been confirmed dead, mostly from carbon monoxide poisoning, and hopes are fading of pulling out any more alive of the 100 or so still thought to be inside.
Anger has swept a country that experienced a decade of rapid economic growth under Prime Minister Tayyip Erdogan's Islamist-rooted government but still suffers from one of the world's worst records of workplace safety.
Furious residents heckled Erdogan on Wednesday as he toured the town, angry at what they see as the government's coziness with mining tycoons, its failure to ensure safety and a lack of information on the rescue effort.
Access to the mine entrance was blocked by paramilitary police roadblocks several kilometers away for a visit by President Abdullah Gul on Thursday. Officers searched cars.
"We came here to share the grief and wait for our friends to come out but we were not allowed. Is the president's pain greater than ours?" asked Emre, an 18-year-old trying to get to the mine who said friends from his village were still trapped.
Erdogan, who announced three days of national mourning from Tuesday, expressed regret for the disaster but said such accidents were not uncommon, and turned defensive when asked if sufficient precautions had been in place.
Newspaper Radikal published an amateur video clip on its website appearing to show Erdogan saying "Come here and jeer at me!" as he walked through a hostile crowd in the town.
A picture doing the rounds on social media of one of his deputy personal assistants, Yusuf Yerkel, kicking a protester as he was wrestled to the ground by armed special forces officers did little to help the prime minister's image.
Colleagues in Erdogan's office defended Yerkel, saying the protester had traveled to Soma deliberately to cause trouble. London's prestigious School of Oriental and African Studies (SOAS), where Yerkel once studied, issued a statement saying it had no association with him after being besieged with enquiries.
"I am sad I was not able to maintain my composure despite all the provocations, the insults and attacks to which I was exposed on that day," Yerkel later said in a statement.
OUT OF TOUCH
Erdogan, who is expected to stand in a presidential election in August, has weathered mass protests and a corruption scandal over the past year, yet his AK Party dominated local polls in March despite the political turbulence.
But his handling of a disaster hitting the sort of working class, conservative community which makes up the core of his supporter base is further evidence, his opponents say, that he is a leader increasingly out of touch.
Gul, a co-founder of Erdogan's party but known for a less abrasive style, struck a more conciliatory tone, saying Turkey needed to review regulations to bring them in line with other countries.
"The pain of every single person is the pain of all of us," Gul said. "Such suffering should not be happening. Just like the advanced countries which no longer go through this, we have to re-evaluate our rules and take all the necessary measures."
Four of Turkey's labor unions called for a national one-day strike, furious at what they see as a sharp deterioration in working conditions since formerly state-run mines including the one in Soma were leased to private firms.
Several thousand people demonstrated peacefully in Istanbul, holding banners with slogans including: "It is not an accident, it is not fate, it is murder" and "Our hearts are burning in Soma". Some staged a sit-down protest in front of police lines.
Police fired water cannon to break up a demonstration in Izmir, the nearest large city to Soma, and there were reports of protests in the southern cities of Mersin and Antalya.
Around a thousand people from various trade unions gathered in Ankara to march on the Labor Ministry, some wearing miners' helmets and waving banners showing the image of Che Guevara.
"The fires of Soma will burn AKP," and "AKP murderers" they chanted, as police looked on.
Thousands gathered after noon prayers for the funerals of more than 40 of the mine workers at Soma's main cemetery, where more than a hundred tightly packed graves have been newly dug. Much of the population around the town either works in or has relatives employed by the mining industry.
Loudspeakers on street corners used by the local government to announce news, left from the days when Internet connections and mobile phones were rare, broadcast the names of the dead and announced funeral times.
The graveyard was so crowded with back-to-back burials that the imam repeatedly had to ask families to pay their final respects quickly to make room for other mourners.
No government officials were in attendance.
"They say they are deeply sorrowed, their hearts are burnt, devastated. Where are they now?" said Emine, a woman in her 50s attending her nephew's funeral.
"Look at all these poor people whose sweethearts died digging money for others. They are alone here."
The rescue operation was hampered overnight as the fire inside the mine continued, making it extremely hazardous for crews to retrieve bodies. Ventilation systems which pump fresh air into the mine were relocated to allow teams back inside.
The fire broke out during a shift change, leading to uncertainty over the exact number of miners trapped. Energy Minister Taner Yildiz initially said 787 workers had been in the mine. Erdogan said on Wednesday around 120 were still thought to be trapped.
Turkey's safety record in coal mining has been poor for decades, with its previous worst accident in 1992, when a gas blast killed 263 workers in the Black Sea province of Zonguldak.
The operator of the Soma mine, Soma Komur Isletmeleri, said some 450 miners had been rescued and that the deaths were caused by carbon monoxide. It said the cause of the fire was unclear.
Initial reports suggested an electrical fault, but Mehmet Torun, a former head of the Chamber of Mining Engineers who was at the scene, said a disused coal seam had heated up, expelling carbon monoxide through the mine's tunnels and galleries. (Additional reporting by Humeyra Pamuk and Daren Butler in Istanbul, Jonny Hogg in Ankara; Writing by Nick Tattersall; Editing by Giles Elgood and Peter Graff)