Rescue teams have found the bodies of 28 miners missing after a methane gas explosion caused a major coal mine in Turkey to collapse three days ago.

Turkey’s energy minister, Taner Yildiz, said rescuers are trying to reach two more trapped miners at the state-run Karadon coal mine near the Black Sea port of Zonguldak, in Turkey’s north.

About 40 miners were reportedly working in two separate areas of the pit at a depth of about 540m when the explosion occurred on 17 May.

Ten miners were evacuated shortly after the explosion.

Rescue operations had been held off since 17 May when a passageway dug by rescuers collapsed. A high build-up of methane raised fears at the time that another explosion could occur.

An investigation has been launched to find if safety violations had any part in the explosion.

It is not the first large-scale mining event to rock Turkey. More than 60 people have been killed in mining accidents in the last six months.

The country’s worst mining disaster happened in 1992, when 270 workers were killed in another mine near Zonguldak.