The group's official news agency then claimed responsibility for the attack and jihadists praised the attacker on Twitter, changing their profile pictures to a photo of Mateen. The gunman, Omar Mateen, reportedly pledged allegiance to the Islamic State before the shooting. The hacker who's been active for several months in defacing and deleting pro-ISIS accounts, launched his new operation following the mass shooting in an Orlando nightclub that left 49 people dead.
Orlando attack is a 'wake-up call' to stop dehumanizing LGBT people, advocates say
