An Australian miner amputated his arm with a craft knife when he became pinned beneath a tractor two miles underground.

Colin Jones, 43, cut his arm off below the elbow rather than wait for rescue services to reach him in a coal mine near Lake Macquarie, on the coast of New South Wales. Doctors later tried to reattach it, but without success.

Mr Jones was trapped on Saturday night after the vehicle, which was carrying three tons of limestone dust, tipped over. Police said yesterday that it was thought to have hit a hole on a sharp bend.

Other workers at the mine raised the alarm but Mr Jones cut off his arm before help arrived. One of his workmates told The Sydney Morning Herald: "Col asked one of the blokes to do it, but he said he didn't think he could go through with it. I think he was in too much shock to think all that much about it. But he didn't know if there was diesel leaking from the [vehicle] and he knew we all had to get out of there, and get out fast in case there was an explosion."

He was flown to a hospital in Newcastle, 95 miles north of Sydney, where doctors were unable to reattach the arm because it was too badly crushed. A hospital spokesman said yesterday that his condition was stable.

Michael Kenny, the local area commander of Lake Macquarie police, said that Mr Jones might have amputated his arm because he was worried about being crushed. He said police were investigating the accident.

Mr Jones became trapped at West Wallsend colliery at about 10.30pm. A spokesman for the ambulance service, Ben Lynch, said that Mr Jones had already cut off his arm by the time emergency crews arrived. He said: "Paramedics stabilised the patient underground before removing him to the surface."

Glen Lewis, general manager at the colliery, said Mr Jones had been trapped under the vehicle for a few minutes.

Les Yates, an official of the mining union, the Construction, Forestry, Mining and Energy Union, said: "They were unable to save his arm because of the extent of the crush injuries."

WorkCover, the state's body in charge of workplace injury and compensation, is investigating the incident.

The mine owners declined to comment until an investigation had been completed.

In May, an American rock climber, Aron Ralston, cut off his right arm at the wrist with a pocket knife after a boulder fell on him in a remote Utah canyon. Mr Ralston, who had waited for help for five days, then abseiled down a sheer rock wall to the canyon floor.