Kiev  - Rescuers found two miners Monday morning, though dozens remained trapped underground after a gas explosion in a coal mine in the Ukrainian region of Donetsk, according to Ukranian television.

It remained unclear how many of the 35 miners survived Sunday's methane gas explosion, 1,000 metres below the surface, but voices of some survivors were heard at a depth of 700 metres, officials said.

The rescuers are racing against time amid fears of flooding in the Karl Marx mine in Yenakiyevo, 60 kilometres north-east of the regional capital Donetsk.

According to executives of the coal company Orzhonakidzeugol, the mine was lightly manned at the time of the explosion as it had been closed Saturday due to safety considerations.

Ukrainian coal mines are among the most dangerous in the world due to the lack of safety measures.

The Ukrainian government has in recent months closed dozens of mines due to the high number of fatal accidents, but dozens of sub- standard mines continue to operate due to high demand for coal from the country's steel and energy industries.

Ukraine's worst-ever coal mining accident took place in 2007 in the Donetsk region's Zasyadko mine, killing 101 miners in an accidental methane blast.

Ukraine's coal mining industry claims on average between 250 and 350 lives every 12 months, mostly in underground explosions and equipment failures. (dpa)