The rescue of 24 miners still missing in a Siberian coal mine accident has been halted because of fears of a new blast.

Two methane explosions shook the Raspadskaya mine in Kemerovo late on 8 and 9 May, shattering the main shaft and a five-storey building at the mine head and killing 66.

The concentration of volatile methane gas in the mine is rising and at some points can reach 7% while a methane concentration of only 1% is considered to be unsafe.

Several sizable fires are also burning about 1,500ft underground, adding to the mine’s danger.

Rescue operations will resume only after the gas concentration is reduced and fires are put out, Russian Ministry official Pavel Plat told Associated Press.

The Raspadskaya mine produces about 10% of Russia’s coking coal and a long interruption of production could disrupt supply of raw materials affecting Russia’s steel industry.