Several people were killed and others injured after an explosion in a bar in the Swiss ski resort of Crans-Montana, BBC reported on Thursday, citing police.

According to a Reuters report, at least 10 people are dead.

Crans-Montana is a luxury ski resort town located in the heart of the Swiss Alps, approximately two hours from the Swiss capital of Bern.

The blast occurred at 1:30 a.m. (00:30 GMT) in a bar called the Constellation, police said in a statement to the BBC.

Footage on social media, apparently taken from the road outside the bar, shows a fire inside a building. We are working to verify these images.

Swiss news outlet Blick suggests the fire may have been caused by fireworks during a concert - but police say the cause is unknown.

Reuters could not immediately verify the report.