After a mining accident in a hard coal mine in Poland, four buried miners died.
Poland's Minister for State Holdings, Jacek Sasin, announced on Twitter on Wednesday that a search is being made for seven other people.
According to the Polish news agency PAP, three miners died underground and the fourth succumbed to his injuries after being taken to hospital.
A methane gas explosion occurred in the mine in Pniowek, Silesia, south of Kattowitz, shortly after one in the morning.
The explosion occurred a thousand meters underground.
At that time, according to the operator, 42 miners were near the site of the accident.
Most of them were taken to the hospital with burns.
According to the information, another explosion probably occurred while rescue teams were looking for three missing miners.
The crisis team then lost contact with several rescuers.
Thirteen rescue teams are currently searching for the missing.
The local fire brigade said rescue helicopters were also in action.
Prime Minister Mateusz Morawiecki wanted to visit the scene of the accident on Wednesday.