Emergency teams on Monday rescued 23 miners after a powerful explosion at a coal mine in eastern Ukraine but at least 13 others remained trapped, an official said.
The teams went deep into the mine in the eastern Donetsk region to rescue 21 miners after earlier helping two to safety following the methane blast late Sunday, said Maryna Nikitina, a spokeswoman for Ukraine's industrial safety watchdog agency. Rescuers also recovered one dead body, AP reported.
The miners were working some 1,000 meters (3,300 feet) underground to improve safety conditions at Karl Marx mine at the time of the blast.
Rescue teams heard the voices of some of the trapped miners when they attempted to get to them through a damaged shaft, Deputy Prime Minister Oleksandr Turchynov told Ukrainian television Sunday.
"There is hope they are alive," he said, adding that the ventilation system in the mine is still working.
The explosion also injured five workers who worked above ground. They were hospitalized with severe burns.
The state-run mine -- where another explosion killed seven in 1999 -- had been declared too dangerous to operate, and the trapped miners were underground to improve safety conditions, officials said.
Ukraine has some of the world's most dangerous mines because of outdated equipment and poor safety standards. Since the 1991 Soviet collapse, more than 4,800 miners in Ukraine have been killed. Officials say that for every 1 million tons of coal brought to the surface in Ukraine, three miners lose their lives.
Coal-rich Donetsk is about 640 kilometers (400 miles) southeast of the capital, Kiev.