Story highlights Video shows a person approaching the building, followed by a flashPulse nightclub shooter Omar Mateen killed 49 people in June(CNN) A fire at the Florida mosque where Pulse nightclub shooter Omar Mateen had prayed was deliberately set, the St. Lucie County Sheriff's Office said. Mateen, who killed 49 people at the Orlando nightclub in June, had attended the mosque. Video shows a person approaching the side of the mosque, followed by a flash. The person is then seen fleeing, Maj. David Thompson of the sheriff's office said. Photos released by the sheriff's office showed the structure appeared to be intact.

Source: CNN September 12, 2016 09:33 UTC