The graves were being dug long before all the bodies had been brought up. By early Wednesday afternoon, 24 hours after the blast ripped through the mine in Soma, western Turkey, a neat row of graves had been prepared at a nearby cemetery.

As some laboured chest deep in the dark soil, others prayed.

Meanwhile, at a hastily established co-ordination centre near the mine, family members scanned images of corpses on computer screens, dreading the possibility of identifying their husbands, brothers and sons.

By then, they knew to expect the worst. The energy minister, Taner Yildiz, had earlier warned that the "problem is more serious than we thought" – and that hopes were diminishing for the success of the rescue operation. At least 245 bodies had been recovered, but rescue workers feared that scores more remained buried.

The disaster, said Yildiz, was developing into an accident "with the highest worker death toll Turkey has seen so far. We are worried that human loss could increase".

Grief was evident on the faces of those who had flocked to the mine as soon as word of the explosion spread and had waited through the night and the following day. But agony was mixed with anger in a country which is one of the most dangerous in the world for mining accidents.

Rescue teams braved flames and gas to try to reach men trapped deep below ground and far from the mine's entrance. Some were brought out, faces black with coal dust and smoke, wrapped in blankets, carried on stretchers, but alive, in the early hours of Wednesday. After dawn, the mine spat out only the dead.

Nearly 800 had been in the pit at the time of the explosion, more than usual due to a shift change. The blast blew power supplies to lifts and conveyors, and started a fire. Most of the dead were killed by carbon monoxide poisoning, officials said, despite frantic efforts to pump oxygen into the mine.

As hundreds of distraught relatives gravitated towards the mine entrance, security forces erected barricades and human cordons to allow rescue workers to do their grim job. Those nearest the entrance to the pit craned to catch a glimpse of those carried out; some rescue workers peeled back blankets shrouding victims' faces. The corpses were as black as the coal they had worked on.

One man told the Associated Press he had led a 10-man team about half a mile down the mine into the tunnels and had recovered three bodies. But his men had to flee because of smoke from coal set alight by the explosion, he said.

Another man walked weeping down the stairs from the mine's entrance. Behind him, two groups carrying heavy stretchers pushed through the crowd. A rescue worker who emerged injured but alive was whisked away on a stretcher to the cheers of onlookers.

Tents were pitched at the entrance to the mine, possibly for use as temporary mortuaries. One elderly man wailed after he recognised one of the dead, and police restrained him from climbing into an ambulance with the body.

Many relatives sat silently on benches in shock, while others scoured a list of the wounded posted up on a wall alongside the name of the hospital they were taken to. One young woman, Bahar Galici, stared at the sheet of paper before walking away. "Still nothing," she sighed.

Harun Unzar, a colleague of the missing miners said he had lost a friend previously. "But this is enormous. All the victims are our friends," he told Agence France Presse. "We are a family and today that family is devastated. We have had very little news and when it does come it's very bad."

One 30-year-old man, who declined to give his name, said he rushed to the scene to help find his brother. "There is no hope," he said with tears in his eyes.

Emine Gulsen was in a group of women who sat wailing near the entrance to the mine. Her son, Mehmet Gulsen, 31, has been working in the mine for five years. "My son is gone! My Mehmet," she cried.

Outside the nearby state hospital, more families sat on the ground, settling in for a long wait. Many of the women sobbed; others sat in shocked silence. Engraved on the entrance wall of the emergency clinic were the words: "For those who give a life for a handful of coal."

One elderly woman, Sengul, whose two nephews worked in the mine along with the sons of two of her neighbours, said: "We haven't heard anything from any of them, not among the injured, not among the list of dead. It's what people do here, risking their lives for two cents … they say one gallery in the mine has not been reached, but it's almost been a day."

Refrigerated trucks and a cold storage warehouse usually used for food became makeshift morgues. Every so often, medical staff emerged to read the names of survivors being treated, as families and fellow workers clamoured for information.

"This isn't a huge city. Everyone has neighbours, relatives or friends injured, dead or still trapped. I am trying to prepare my family for the worst," said Hasan Dogan, 27, watching TV news reports from a canteen set up outside the hospital.

Meanwhile, Soma was bracing itself to take the premier position in the league table of Turkish mining disasters. As the waiting families settled in for another night of desperate waiting, it seemed inconceivable that the final death toll would not exceed the 263 victims of a pit explosion in Zonguldak in 1993.

Sitting on the pavement outside the hospital, Hatice Ersoy, 43, said: "They haven't brought any ambulances in such a long time that we've started to lose hope."