Riot police fired tear gas and water cannon to disperse several thousand protesters on Friday in a Turkish mining town still grieving the death of some 300 workers in the nation's worst ever industrial disaster.

Anger has swept Turkey as the extent of the disaster became clear, with protests aimed at mine owners accused of ignoring safety for profit, and at Prime Minister Tayyip Erdogan's government, seen as too cozy with industry tycoons and insensitive in its reaction to the tragedy.

"Stop spraying us with water! Go spray the mine! Maybe you can finally put the fire out!" shouted one man among the crowd, which had been trying to march towards a statue in the town honoring miners when police blocked the route and sprayed from armored trucks.

The confirmed death toll in the disaster reached 292 as Energy Minister Taner Yildiz said eight more bodies were found in the mine on Friday evening. Some 10 more people were believed still trapped and unlikely to be alive, three days after fire sent deadly carbon monoxide coursing through the mine.

Turkey has experienced a decade of rapid economic growth under Erdogan, but worker safety standards have failed to keep pace, leaving it with one of the world's worst industrial accident records.

"No coal can warm the hearts of children whose fathers died in the mine," read one hand-written sign in the crowd of mine workers and residents.

The police intervention in the mourning town could add to public anger towards Erdogan. He survived mass demonstrations and a corruption probe into his government over the past year to remain Turkey's dominant politician, but he now risks alienating conservative, working-class voters that form his party's base.

Footage emerged of him apparently slapping a man as residents jeered and jostled his entourage when he visited Soma this week. The man, Taner Kuruca, said Erdogan had indeed slapped him and told Kanal D TV he was then beaten by the prime minister's bodyguards.

A spokesman for Erdogan's Justice and Development Party said there was no visual evidence of Erdogan striking anyone, while his adviser Yalcin Akdogan, writing in the Star newspaper, accused "gang members" of provoking the prime minister's team as he went to meet mourning families.

Police have clashed with protesters in Turkey's three biggest cities Istanbul, Ankara and Izmir in recent days. Anger was intensified by a photograph of an Erdogan aide kicking a protester held down by police special forces.

Officials from the mine held a tense news conference, giving their most detailed account so far of what had happened. An unexplained build-up of heat was thought to have led part of the mine to collapse, fanning a blaze that spread rapidly more than a mile below the surface, the mine's general manager Ramazan Dogru told a news conference.

"It was an unbelievable accident in a place where there have been very few accidents in 30 years," Soma Holding Chairman Alp Gurkan said. "A mine with top level miners, accepted as being the most trustworthy and organized."

Opponents of Erdogan blame the government for privatizing leases at previously state-controlled mines, turning them over to politically connected businessmen who they say may have skimped on safety to maximize profit.

Thousands gathered after noon prayers on Thursday for mass funerals at Soma's main cemetery, where more than a hundred tightly packed graves have been newly dug. Efforts continued to retrieve those still trapped.

Energy Minister Taner Yildiz said a team of inspectors and prosecutors had entered parts of the mine that were safely accessible to begin an investigation.

Plant manager Akin Celik said there was no question of negligence on the part of the company. Gurkan was more cautious, saying he would wait for an inquiry led by the Labor Ministry.

"If there is neglect within the operations, a mistake, a shortcoming, I'll follow up legally to ensure those responsible are punished," he said, adding a foundation would probably be established to pay compensation to the families of the dead.