An attempted armed robbery on a bookies ended in tragedy when the masked gunman collapsed and died after being pinned down by customers.
The man, in his 50s, burst into the Ladbrokes branch in Plymouth, England shortly before 7pm on Friday, wearing a gas mask and brandishing a gun.
A group of customers immediately tackled the man, disarming him and pinning him to the floor while others raised the alarm.
Police officers called to the scene found the man already unconscious. They called for an ambulance and tried to revive him, but he was declared dead a short time later.
Devon and Cornwall police have referred the incident to the police watchdog, the Independent Police Complaints Commission (IPCC), who will conduct their own investigation.
A police spokesman said: “It quickly became clear the man was unresponsive and an ambulance was immediately requested by police who carried out CPR until they arrived.
“A few minutes later three paramedics arrived at the scene and continued to carry out further CPR. Around 20 minutes later the man was declared dead at the scene by the paramedics.”
Customers have spoken of their shock at the turn of events. David Walker, 54, who had gone into the bookies to bet on foreign football matches, found two men subduing the suspect and assumed it was a fight.
Mr Walker said: “When I walked in they were on the floor. They were scuffling but I just thought it was a fight. There were two men, customers I think, on top of him and the bloke on the floor.
“The staff were behind the counter and an old man was standing around. The bloke from behind the counter told me they weren’t taking any bets and I had to go. I didn’t see their faces as they were holding the guy down at the back of the shop.
“They said someone came in to rob the place. I couldn’t see any mask. I couldn’t see his face. There were no physical movements, they were just holding him down.”
Ivor Green, 67, from West Park, said he was not surprised at all that the customers had leapt to the defence of the staff.
"They would do that in a shop like this, it is our betting shop," he said. "The staff become your friends, it's a little family, and it's no different to a member of your family being threatened. The guys in there would be protective of them.
Scenes of Crime officers remained at the scene into the night as a full investigation into the incident was launched.
Forensics experts wearing protective clothing have been working inside the building, which remained taped off into the early hours of Saturday morning. A HM Coroner van was seen leaving the scene shortly before 11pm on Friday night.
The man has been identified but next of kin have not yet been informed, police said.
Chief Inspector Ian Drummond-Smith said: “This is a very serious incident. We cannot speculate on what has actually taken place here.
“A full investigation has now begun and while the IPCC carry out their investigation it is not appropriate to comment further.”
The two storey Ladbrokes remained closed on Saturday as uniformed police stood guard. A spokesperson for the betting chain said: “We’re assisting police with their investigation and it would be inappropriate to speculate any further at this time.”