Multiple news outlets reported on Monday that the gunman who carried out the Orlando terrorist attack frequented the LGBTQ nightclub where he killed at least 49 people.

He also used multiple gay-dating apps, according to several people who had communicated with him on the apps.

And one of his former classmates told The Palm Beach Post that he believed Mateen was gay – something federal investigators are now reportedly looking into – and that Mateen once asked him out romantically.

The new developments about 29-year-old Mateen complicate his likely motives and his pledge of allegiance to ISIS – aka the Islamic State, ISIL, or Daesh – the terrorist group that has been known to throw gay people off of rooftops.