Mauricio Garcia, 33, had a profile on a Russian platform. In a video posted on the day of the attack, he removed a mask from the movie "Scream" and said: "It's not exactly what you expected, huh?", NBC News reports.
Garcia had multiple weapons, including an AR-15 rifle and a handgun, when he opened fire at a crowded outdoor mall in the Dallas suburb of Allen. Authorities have not disclosed a motive for the mass shooting, but a law enforcement source said Garcia's social media profile is part of the investigation.