FBI investigating whether Orlando killer was a club regular

ORLANDO, Fla. (AP) — The FBI is investigating reports that Orlando gunman Omar Mateen had been a regular at the gay nightclub he attacked and had used gay dating apps, a U.S. official briefed on the case said Tuesday.
A number of possible explanations and motives for the bloodbath that left 49 victims dead have emerged, with Mateen professing allegiance to the Islamic State group, his ex-wife saying he was mentally ill, and his father suggesting he was driven by hatred of gays.