A tourist helicopter with 16 people on board plunged into a deep volcanic crater lake on the Kamchatka Peninsula in Russia’s far east on Thursday, writes Euronews.

Rescuers were searching in the lake for up to eight people missing, officials said, while at least eight others reportedly survived.

The helicopter crashed in the Kronotsky Nature Reserve, and the regional administration said workers were searching for survivors in Kurile Lake, which was formed in a volcano caldera and crater.

Russia’s Emergencies Ministry said 13 tourists and three crew members were aboard the Mi-8 helicopter and eight people survived. It said two of them were heavily injured.