Around 35 mine staff were trapped about 700 metres below ground, two of them injured, after an unexplained blast in a potash mine in eastern Germany, the Mitteldeutsche Zeitung news website reported, citing a spokesman with the state mining authority.
The local broadcaster MDR reported that a rescue operation had begun.
The staff were located in a safe sector of the mine in Teutschenthal, about 150 km (95 miles) southwest of Berlin, and were being supplied with oxygen.
The mining authority said one of the injured was in a serious condition, the other only lightly injured, and that there was a possibility that they could be brought to the surface through a shaft that was intact.
The mine is no longer active but is being used to deposit mining waste from elsewhere, the website said.