WARSAW (Reuters) - Rescuers searching for three Polish miners trapped almost a kilometre underground since a tunnel collapsed eight days ago have found two bodies, taking the death toll from the incident to four, coal company JSW said on Sunday.

One man is still missing at the Zofiowka mine in southern Poland, which was struck by an earthquake on May 5, initially trapping seven miners. Two were found dead and two others were rescued early last week.

“Rescuers have found the body of the second miner ... The action continues, one miner is still being sought,” JSW, the European Union’s biggest coking coal producer, said in a statement.

The bodies were found as rescuers were pumping out water from the flooded mine.

Around 1,000 people have been involved in the rescue action, JSW said, adding it was one of the most difficult in the company’s history.

About 250 people were working underground at the time of the quake. The missing miners were in a team drilling a new tunnel.

The 3.5-4.0 magnitude quake was the strongest recorded in the mine, officials there said.

Around 83,000 people work in Poland’s coal mining sector. Fifteen people died in mining-related accidents in 2017, and eight have died so far this year.