Slovakia – An explosion in a northern Slovak coal mine most likely killed 20 miners on Monday in the central European country's worst mining disaster.

Rescue teams found six dead bodies after about 12 hours of efforts in poor visibility and high temperatures, officials said.

The rest of the missing group were also presumed dead because conditions in the shaft were not fit for survival.

According to a report from mine rescuers all the 20 miners died, Economy Minister Lubomir Jahnatek said at the site of the accident in Handlova, about 195 km (120 miles) northeast of the capital Bratislava.

Rescue workers are now 65 meters from the center of the blast, six bodies were founds at this place.

The workers had been putting out a fire in the Handlova mine when the explosion occurred, the mine operator said.

Hornonitrianske Bane Prievidza, the biggest mining firm in the country, said the explosion tore through an unused section of the pit, about 330 meters (1,080 ft) below the surface, at 9.30 a.m. (0730 GMT).

At that point, all contact was lost with the crew underground.

All the presumed victims were Slovak nationals, mine director Peter Cicmanec said. Many foreigners, mainly Poles, work in Slovakian mines.

Most likely the source of the blast was gases left over from imperfect combustion from the fire, Cicmanec said.

He said small fires of self-igniting coal were frequent in the mine, and there were several of them in the past days.

Relatives and friends of the missing miners congregated at the mine throughout the day to await news from the emergency teams.

A 25-year-old Radoslav, whose father was one of those presumed killed, said during the rescue efforts that officials had told the relatives already in the afternoon that there seemed to be little hope.

They told us to prepare for the worst, he said.

Nine other miners suffered light injuries and were discharged from hospital after treatment.

Twelve people have been killed in previous mine accidents in Slovakia, a member of the European Union and the euro zone, in the past dozen years.

Prime Minister Robert Fico and several government ministers travelled to the site to oversee the rescue effort. Fico said he would convene the cabinet on Tuesday to discuss aid and order a national day of mourning.

This is a great tragedy, Fico said. The government is ready to provide financial aid as well.

(Writing by Jan Lopatka; editing by Angus MacSwan)

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