March 7 (Reuters) - An early morning explosion at a nightclub in northwestern Peru injured at least 31 people, authorities said on Saturday.
The government of Peru's La Libertad region said hospitals were treating individuals after the blast at the nightclub in Trujillo, which authorities are investigating.
Four people are in grave condition, the newspaper La Republica said, citing the regional health authority, which said minors were among those injured.
It is unclear what caused the incident. Peru has experienced a surge in violence related to organized crime, and Saturday's incident follows smaller attacks on nightclubs in Trujillo, according to local media reports.
The explosion occurred during a show by a Peruvian musical group and sent revelers running for safety.
Members of the Amor Rebelde group were unhurt after what they said were "unfortunate events" that occurred at the nightclub where they performed, according to a statement from the group on Facebook.
Video shared on a Peruvian news program showed scenes of chaos after a loud boom was heard.
(Reporting by Brendan O'BoyleEditing by Rod Nickel)
