By Duarte Garrido, Entertainment Reporter
At least five people have been killed after a lone gunman opened fire at the BPM Music Festival in Mexico.
Mexican police said at least a dozen others were wounded at a nightclub in the Playa Del Carmen resort.
Glasgow DJ Jackmaster, who was headlining at the Blue Parrot club in the early hours on Monday, tweeted: "Someone has come into the club in Playa Del Carmen and opened fire."
He said he believed there were four or five people dead and "many wounded", before warning people to stay inside their hotels.
Two Canadians, one Italian and a Colombian were killed in the shooting, according to Miguel Angel Pech, Quintana Roo state's attorney general.
The fifth victim died in a stampede which started when the gunfire began.
Four people have been arrested over the shooting.
According to MixMag magazine, whose reporters were tweeting from the festival, a second shooting was reported at another club called The Jungle, where a separate closing party was being held.
Valerie Lee, the magazine's US editor, said she heard "at least four to five shots fired" at the Blue Parrot.
"People started running because there's an exit in the back," she said. "We stopped and hid behind a cement wall, then crawled under a metal table.
"Security guards at first didn't think it was shots and kept claiming it was fireworks, saying everything was okay.
"Then people kept running and said they saw a gun. We kept hiding until they opened the back gate and we ran outside."
Local media reports suggest the shooting may be connected to Mexico's ongoing wars between drug cartels.
The official Twitter account of the BPM Festival published a tweet, which has since been deleted, saying "all parties are shut down".
The BPM Music Festival, popular among foreign tourists, takes place in several venues across Playa Del Carmen in Mexico, featuring more than 150 of the world's top DJs.
The 2017 event marked the festival's 10th anniversary.