A murder investigation has been launched at the Burning Man festival in the US state of Nevada after a man was found "lying in a pool of blood" on Saturday night, police say.

A festival-goer stopped a police officer at around 21:14 (04:14 GMT) to alert him about the incident and the man was found "lying on the ground, obviously deceased" at a campsite, Nevada's Pershing County Sheriff's office said.

The body was discovered as the Man - a towering structure which lends the festival its name - was beginning to burn. The victim's identity is not known.

Burning Man Project said it was co-operating with law enforcement and urged those at the festival not to interfere with the investigation.

Part of the site in the Black Rock Desert was cordoned off as on-site police began investigating alongside a forensics team.