New details are emerging following the tragic shooting at a movie theater in Louisiana.
ET has learned that John Russell Houser was sitting in the last row of the theater when he stood up and started firing shots about 20 minutes into a screening of Amy Schumer's comedy Trainwreck at Grande Theatre in Lafayette.
WATCH: Amy Schumer Reacts to Trainwreck Theater Shooting
Houser reportedly fired off 13 shots from his handgun, with one male being hit seven times. Two victims, 21-year-old Mayci Breaux and 33-year-old Jillian Johnson, died and nine more were hospitalized, according to Lafayette Police. As of Friday evening, four have been released and one remains in critical condition.
After the spree, Houser attempted to leave the theater through a side door but was forced back inside by police. He reloaded his gun as an officer arrived on-scene, returned to the screening room and shot himself inside the theater. He died at the scene, where 15 castings have been found.
Johnson, who died at a local hospital, was shot twice in the back as she attempted to exit the theater, a source tells ET.
Her husband Jason shared a heartfelt note in her honor. "Our hearts are shattered," he wrote on their store Red Arrow Workshop's Facebook page. "We will love you forever. She was a once-in-a-lifetime gal. A mother, daughter, sister and a truly exceptional wife. She was an artist, a musician, an entrepreneur and a true renaissance woman. She was the love of my life and I will miss her always."
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"Our thoughts are with the family of Mayci Breaux," he added. "We mourn with you. And finally our thoughts and prayers are with Jillian's best friend, who was in the theater with her at the time of the shooting. We love you and we're wishing you the best! This was a senseless act and, as is the case with all such acts, there is no playbook, no rules on how to cope. We're trying our best to pull ourselves together."
While there are surveillance cameras at the theater, none were located inside of screen 14, where Trainwreck was being shown. There is, however, video of Houser "purchasing a ticket normally and proceeding into the lobby of the movie theater," according to ET's source.
Houser, 59, was described by cops as a drifter who had checked into a Lafayette motel room earlier in July. His last known address was 500 miles away in Phenix City, Alabama, the same town he had legally purchased the gun used in the shooting last year. Wigs and glasses, which the police consider disguises, were found in his rented room. Houser had also parked his blue 1995 Lincoln outside of the theater’s exit door, presumably for a quick escape, according to Lafayette Police Chief Jim Craft.
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ET spoke to friends Jonah Slason and Heather Hamilton, who were in the screening at the time of the shooting. They were the first to leave, running out of the theater and never looking back. "I felt violated," Slason said. "I felt confused."
Director-producer Judd Apatow and Schumer have both shared their condolences since the shooting.
"One of the reasons we make these movies is because the world can be so horrifying and we all need to laugh just to deal with it," Apatow said in a statement to ET on Friday. "So to have this happen in a room where people were smiling and laughing devastates me. My thoughts and love go out to the victims and anyone touched by this madness or any madness. We, as a country, need to find a way to do better."
Schumer took to Twitter to share her "thoughts and prayers":
Watch the video below for more information on the shooting.