Four Polish miners killed in pit accident

JASTRZEBIE ZDROJ, Poland (Reuters) - Four miners have been killed and 19 others injured in a methane explosion in southern Poland, officials said on Thursday.

The explosion took place late on Wednesday at the Borynia mine in Jastrzebie Zdroj near the Czech border.

"Some of the wounded are in a serious condition," said Katarzyna Jablonska-Bajer, a spokeswoman for the company that runs the mine. "This was a methane explosion. Unfortunately we do not know what caused the accident as all the sensors were destroyed."

She said there had been no sign of increased methane concentration prior to the blast.

"This is a tragedy for all of us. I worked on the same shift (as those who were killed). I am very sad," miner Tomasz Lisiak told Reuters.

Accidents in Polish coal mines are not uncommon. Two years ago, more than 20 men died when a methane explosion ripped through their mine in Poland's southern coalbelt region in the worst such accident since 1979.

(Reporting by Janusz Chmielewski; editing by Gareth Jones)