At least 37 miners in Ukraine were trapped underground following a powerful explosion during maintenance work at a coal mine in the eastern city of Donetsk. Officials say the blast destroyed the main shaft of the mine. Stefan Bos reports for VOA from Budapest.

Ukrainian rescue teams are trying to reach dozens of miners who remain trapped about 1,000 meters underground after a blast at the Karl Marx mine in the eastern city of Donetsk.

Officials say at least four other workers above ground have been injured in the explosion, including three women who were taken to hospital with severe burns.

Speaking on Russia Today  television, Coal Industry Minister Viktor Poltavets says the explosion occurred during maintenance work at the 110-year-old mine.

"This was a repair job," said Viktor Poltavets. "They were about 37 people there. People were about to leave when the blast occurred at around 5:00 am local time."

Minister Poltavets says rescuers were unable to reach the workers, after unmanned gondolas got stuck about half way down the mine. But he says rescuers are opening lines of communications with the miners.

Officials say it is difficult to reach them as the main shaft of the mine has been destroyed by the explosion.

The blast is not an isolated incident. In November three explosions at another mine killed 106 workers.

Experts say Ukraine has one of the world's most dangerous mining industries, due to outdated equipment and poor safety standards. The government has begun closing mines due to a high number of fatalities.

Since the collapse of the Soviet Union in 1991, more than 4,800 miners are believed to have been killed in accidents. Officials say that for every one million tons of coal brought to the surface in Ukraine, three miners lose their lives.