TORRANCE ( — A Florida man who killed 49 people in a mass shooting at a gay nightclub in Orlando was employed by a British security firm that has several office locations throughout Southern California.

Omar Mateen opened fire at the crowded Pulse Orlando club early Sunday in the deadliest shooting rampage in modern U.S. history. He was killed in a gun battle with a SWAT team after police used explosives and a small armored vehicle to punch a hole in a wall and allow dozens of club-goers to escape, police said.

Mateen was a 29-year-old American-born Muslim who worked as a security guard in Florida. FBI officials said they had investigated him in 2013 and 2014 on suspicion of terrorist sympathies but could not make a case against him.

Mateen had been employed at the G4S company, which has clients in more than 100 countries and identifies itself on its website as “the leading global integrated security company.” He “was subject to detailed company screening” when he was recruited in 2007 and “re-screened in 2013 with no adverse findings”, according to a company statement.

In addition to security solutions firm AMAG Technology in Torrance, G4S has 16 offices located in California, including locations in Los Angeles, Anaheim, Cypress, and Westlake Village.

According to data compiled by Bloomberg, G4S was “consistently one of the biggest contractors with the U.S. federal government after the September 11 terrorist attacks”, primarily with the Department of Homeland Security (DHS) and the State Department. In 2015, G4S contracts with the U.S. government dropped to just over $89 million, Bloomberg reported.

G4S Regional CEO for North America John Kenning issued a statement Sunday saying Mateen was “not on duty at the time” of the shooting.

The FBI has not said whether the agency notified G4S about its investigations, according to Bloomberg.
Daniel Gilroy told CBS Miami that he worked with Mateen at G4S. Gilroy called him an angry, loud, profane man who used slurs for gay people, blacks, Jews and women. “He never used other words to describe them,” Gilroy told the Tampa Bay Times. Mateen also regularly made threats of violence, according to Gilroy.

“I kind of feel a little guilty that I didn’t fight harder,” Gilroy said. “If I didn’t walk away and I fought, then maybe 50 people would still be alive today.

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