Shares in G4S, a UK-based security firm, fell sharply after it was confirmed the gunman who killed at least 50 people in the attack on a gay club in Orlando was once employed as an armed security guard at the company.
Omar Mateen, the man identified as the shooter in the attack, worked with private security group G4S Secure Solutions as an officer in Florida. The role requires 28 hours of classroom training by a licensed instructor.
Shares in the company dropped as much as 8.1 per cent when trading began on Monday.
G4S shares were priced 7.7 per cent lower at 172.90 pence just before 9am in London, reducing the company’s market valued to £2.69bn.
The company’s customers include Nike, IBM, General Motors and Bank of America.
The incident has raised questions over the firm’s security procedures as it struggles to rebuild its reputation after a string of scandals.
G4S stock had already declined 34 per cent in 12 months, falling the most in March as the firm warned shareholders of rising charges from contracts housing 18,000 asylum seekers in the UK.
Last month, G4S suspended seven employees at youth detention centres after allegations that guards used excessive force and one child was stabbed with a fork.
In 2012, the company also failed to supply enough security guards for the 2012 Olympics in London, forcing the army to intervene to make up for insufficient numbers.
On Sunday, John Kenning, regional chief executive officer for North America, said G4S was shocked and saddened by the tragic events.
He confirmed that Omar Mateen had been a G4S employee since September 2007, but that he was off duty at the time of the incident. He also said the company was cooperating with the FBI investigation.
“Mateen underwent company screening and background checks when he was recruited in 2007, and the check revealed nothing of concern. His screening was repeated in 2013 with no findings,” Mr Kenning said.
“We were not made aware of any alleged connections between Mateen and terrorist activities, and were unaware of any further FBI investigations. Our thoughts and prayers remain with the victims of this unspeakable tragedy, and their friends and families,” he added.
Fifty people were killed and 53 wounded in the deadliest mass shooting in recent US history on Sunday.
The 29-year-old assailant, who was born in New York, was equipped with a handgun and an assault rifle.
Twenty minutes into the attack, he called 911 and pledged allegiance to Islamic State.
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