At least five people were killed in a shooting on the closing night of the BPM Festival in Mexico.
Shots were reported just after 3.30am at the popular Blue Parrot club in the popular tourist resort of Playa Del Carmen, just south of Cancun.
Rodolfo Del Angel, director of police in the state of Quintana Roo, where Playa del Carmen is located, confirmed five people were dead and said 15 were injured.
Mr Del Angel said that the shooting was the result of "a disagreement between people inside" the nightclub and said security guards had come under fire when they tried to contain the dispute.
George de Menezes, 22 from Watford, who was in the Blue Parrot nightclub at the time of the shooting, told The Independent: "We were in the Blue Parrot nightclub and literally two metres from us shots started going off.
"No one took it seriously, but I knew straight away that it was a gun and dropped to the floor, then everyone dropped with me.
"The music stopped and so did the shots, so we got up and one man was down on the floor and looked dead, and another man had been shot but was trying to stay on his feet."
He added: "Everyone tried to run out to the beach from the club and all of a sudden we heard another shot and everyone dropped again and it kept going on.
"Finally got out from there and got up to the Main Street and there was another man dead on the street, so everyone started running for their lives."
He said he heard more shots after getting back to his hotel, along with reports of shootings at other clubs.
"We don't know if it's a terrorist attack or something else, but we were the first ones to hit the ground and watched it all unfold.
"If he'd turned on us, we'd probably be dead."
The attorney general of Quintana Roo state said several of the dead appear to have been part of the security detail at the 10-day BPM electronic music festival.
Miguel Angel Pech said a lone gunman apparently entered the nightclub and began to exchange fire with another person inside. Festival security personnel tried to stop the shooting and came under fire.
Mr Pech said it was not any kind of terrorist attack.
But the shooting apparently caused a rush of people heading for the exits at the beach-side club, and the lone female victim was apparently killed during the stampede.
Mr Pech said five of the injured had been treated for less serious injuries at local hospitals and released.
He said three people had been detained nearby, but it was unclear if they had been involved in the shooting.
In an official statement, BPM Festival said the attack involved "a lone shooter."
BPM wrote that "the violence began on 12th street in front of the club and three members of the BPM security team were among those whose lives were lost while trying to protect patrons inside the venue."
Two Canadians, one Italian and one Colombian were among the dead, the AFP news agency reported.
Video footage from the scene shows people outside the club running for safety.
A second shooting is believed to have happened at The Jungle club.
Someone has come into the club in Playa Del Carmen and opened fire. 4-5 dead and many wounded. Stay in ur fuckin hotel if you're here at BPM— JACKMASTER (@jackmaster) January 16, 2017
She said: "We were at Elrow, in the back of the club. We heard what appeared to be gunshots but a worker told us to calm down, it was just fireworks.
"People started getting up and again the shots started. My friends saw the shooter running across the back of the club shooting into it through a metal rail. One of my friends saw a person shot and bleeding."
This is a very very sad situation. Tryna get my head around it still. Thoughts and condolences to all affected ♥— JACKMASTER (@jackmaster) January 16, 2017
She added: "Once the shooting stopped we jumped over that same fence and ran on the beach about 10 blocks.
"We were helped by some other party goers by letting us hang out in their hotel for a few minutes. They saw a guy shot in the head."
A spokesman for the Foreign Office said: "We are seeking information from emergency services in Mexico, following reports of a shooting in Playa del Carmen."
The festival has been running for 10 years and is popular with foreign tourists, especially from the UK and US.
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