MOSCOW (AP) — Russian news agencies say that up to 10 people may have been killed and at least 40 others wounded by a natural gas explosion at a college in Crimea.

The gas canister explosion is said to have occurred Wednesday at the vocational college in the city of Kerch in eastern Crimea, according to local emergency officials.

The Interfax news agency cited local officials as saying up to 10 people might have been killed and about 40 others might have been injured by the blast.

The cause of the explosion wasn't immediately clear.

Russia has annexed Crimea from Ukraine in 2014, a move that triggered Western sanctions.