They've also discovered that Houser, who ultimately died in the screening room after turning his handgun on himself, appeared to have carefully planned his attack.
Investigators found writings in the Lafayette motel room he started renting out at the beginning of July, ET also learned. He had been targeting law enforcement, government entities, abortion clinics and "anyone else will do."
Included in the writings were the name of the movie and showtime, which was ultimately a 7:10 p.m. ET screening of Trainwreck.
Houser methodically shot 11 people total, resulting in two fatalities and nine injuries. As of Saturday afternoon, three of the victims were still hospitalized. The two dead have been identified as Mayci Breaux, 21 and Jillian Johnson, 33.
In a press conference, Lafayette Police Chief Jim Craft said Houser stood up in the movie theater Thursday night and fired a 10-round clip. He then tried to leave the screening and make it to his car, a blue 1995 Lincoln, but re-entered the theater when he saw police arriving in the parking lot.
Once he was back in the theater, Houser reloaded his gun, fired three more rounds and then shot himself in the head. "Out of 20 rounds, he shot 11 people, but some people suffered multiple wounds," Craft said. "One person was shot four times."
Houser legally purchased the handgun he used in the shooting at a pawn shop in Phenix City, Alabama, last year. That town, about 500 miles from Lafayette, was his last known place of residence, and he had been evicted from the home he was staying in there.
The one-time political candidate and law school graduate was described by police as a drifter who had a history of mental problems.
Houser reportedly wrote excessively online about being a "lone wolf." In 2013, a tweet believed to be from Houser stated his affinity for the Westboro Baptist Church, calling it the "last real church in America," adding that "members [were] not brainwashed." The church has since tweeted that they're "warming up the picket signs for #lafayettetheater shooting victim funerals. God Sent the Shooter AGAIN!" They did, however, also write that if Houser had been a follower of theirs, he would have "grabbed a sign, not a gun."
Earlier this afternoon, the Lafayette Police Department shared a photo from the crime scene and sent their prayers to the victims and their loved ones.