A simple smoke alarm installed in a hotel room tipped police off to Stephen Paddock’s location amid the deadliest shooting in US history which saw 59 people die and more than 500 injured.
Las Vegas police lieutenant Randy Sutton said the killer’s room in the Mandalay Bay hotel quickly filled with smoke after he started unloading rounds of ammunition, The Washington Post reports.
It’s believed this helped the SWAT team find Paddock who shot a security guard in the hallway before killing himself.
It saved police checking more than 3,300 hotel rooms.
Lt Sutton said Paddock fired “hundreds of rounds”.
“The sheriff said that there were several firearms found in the room,” he said.
“He was extremely well armed. He must have brought plenty more ammunition, already loaded into magazines.”
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According to the US’s National Air Filtration Association each shot fired “releases a small quantity of harmful dust and gases”.
Gases and particles can build up in firing ranges even where there is appropriate ventilation.