One victim was seriously injured, the other slightly injured, said a police spokeswoman in Halle (Saale), near where the incident occurred in the Saalekreis district. Both have been taken to hospital.

Following an explosion in the mine, about 35 people were trapped underground at a depth of about 700 meters. 

The workers were able to escape to a so-called safety room, where they were supplied with oxygen, said a spokesman for the State Mining Office in Halle on Friday.

According to Halle police on Twitter, all people were rescued safely.

Emergency forces arrived to the site at around 9am, according to a spokeswoman. A large number of rescue workers, as well as the local fire brigade, showed up to the scene. 

The State Office for Geology and Mining was also there to offer assistance for the technically tricky rescue operation.

About 100 people work in the Teutschenthal mine, according to the company. Over the past 15 years, the mine, which was shut down in 1982, has been rebuilt. 

Today, mineral waste is dumped on 14 square kilometers of land. Previously, the mine had been used for potash salt extraction for around 80 years.