A methane gas explosion at Maloivanivska mine in eastern Ukraine has killed at least one worker, with nine others missing.

The explosion occurred in Luhansk People’s Republic’s (LPR) Pervomaisky district, 40km west of the Russian border. Twenty people were working on-site at the time.

According to local officials, the explosion happened 210m underground.

"The chances of finding survivors are not high."

LPR health minister Larisa Airapetyan told Interfax: "The chances of finding survivors are not high: there is a lot of gas in there."

Following the incident, a state of emergency has been declared in LPR. In addition, an emergency situation headquarters and state commission have been created.

A health official said that an exit was blocked as a corridor collapsed when the explosion happened.

Clearance of debris is ongoing, with rescue operation currently taking place.

The Lugansk news site reported police chief Igor Kornet as saying that despite issuing instructions, the mine was not closed.

Previously, the Maloivanivska mine had been stripped of its operating licence due to a number of safety concerns.