A gunman opens fire at the Tree of Life - Or L'Simcha Congregation synagogue in Pittsburgh, Pennsylvania, killing at least 11 people. The perpetrator 46-years old Robert Bowers was an active user of the social media service Gab where he had posted anti-Semitic and racist content as well as one before the shooting that said "HIAS likes to bring invaders in that kill our people. I can't sit by and watch my people get slaughtered. Screw your optics, I'm going in".