Houser stood up Thursday evening in the theater where the comedy "Trainwreck" was showing and fired off one 10-round clip, Lafayette Police Chief Jim Craft said at a press conference.
"This was slow and methodical," Gov. Bobby Jindal said. "This was not a single burst."
Houser left the theater through a side door and headed toward his car, a 1995 Lincoln, but saw a police cruiser arrive in the parking lot, Craft said.
Houser, 59, reloaded his handgun, reentered the theater and fired three more rounds, Craft said.
Then Houser, a law school graduate with a history of mental problems, fatally shot himself in the head, Craft said.
"Out of 20 rounds he shot 11 people, but some people suffered multiple wounds," Craft said. "One person was shot four times."
Two women in the theater were killed and nine were wounded. By Saturday afternoon, three patients remained hospitalized in two area hospitals: two listed in good condition at Lafayette General Medical Center and one in fair condition at Our Lady of Lourdes, according to CNN affiliate KATC
The gun Houser used, a Hi-Point .40-caliber semiautomatic pistol, was legally purchased in February 2014 from a shop in Phenix City, Alabama, Craft said, citing the the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives.
Drew Griffin, a senior investigative correspondent for CNN, said it appears Houser was cleared to buy the gun because he didn't have any convictions for serious crimes.
"He just didn't show up on any of the instant background checks," Griffin said.
Police don't know why Houser opened fire in the theater or why he came to Lafayette, about 500 miles from his stomping grounds in Georgia and Alabama.
Besides an uncle who died about 35 years ago, Houser, 59, didn't have any known connection to the city of 120,000.
He arrived on July 2 or 3 and had been staying in a motel, Craft said. He had just borrowed $5,000 from his mother, said Louisiana State Police Col. Michael Edmonson, but "he needed money."
Craft said authorities think Houser even went to a church in Lake Charles and obtained food and money. He'd been talking to some locals about opening an oil-change business, the chief said.
But he never said or did anything that presaged the outbreak of violence.
Craft said police are researching Houser's movements and reading his journals and his online political blogs, in which he railed against government. There's no indication he had an accomplice, Edmonson said.
At the press conference in the theater parking lot, Jindal, a presidential candidate, was asked what he would do to stem gun violence. He declined to talk about that, saying, "It hasn't been 24 hours. Let's focus on these families."
Acted like any other patron, then randomly opened fire
had a history of legal and mental problems. In 2008, his then-wife took out a restraining order against him, saying she was "fearful of him," police said.
The one-time political candidate from Columbus, Georgia, spent time that year and the next getting treated for mental health issues. Last year, he was evicted from a house he used to own in Phenix City, Alabama, and returned to vandalize the property, the sheriff there said.
On Thursday, he bought a ticket for the 7:10 p.m. (8:10 p.m. ET) showing of "Trainwreck," a romantic comedy. About 25 people were in the screening room and about 300 total in the multiscreen movie complex.
Houser settled into the theater's second-to-last row, which was where Randall Mann's 21-year-old daughter was sitting.
Mann's daughter heard the first pops about 20 minutes in, thinking they could have been firecrackers or part of the movie. But she "knew something was happening" when she saw muzzle flashes, Mann said. She hit the floor and then ran for her life, joining a panicked but controlled, helpful crowd.
Another man in the theater told Keifer Sanders, who was watching another movie, that "there was no argument, nothing going on at all. And a guy just stood up and started opening fire."
"The guy was just kind of at ease, just standing there, just shooting," Sanders said.
the story of two teachers, enjoying the last few days of summer break, caught up in the melee. One jumped over the other
, a move that the friend said prevented a bullet from hitting her in the head, according to the governor. It struck her in the leg instead.
Police said one person played dead once the shooting started.
Colorado shooting happened 3 years ago
There are clues suggesting this wasn't a spontaneous act. Searches of Houser's hotel room and vehicle turned up wigs, glasses and other apparent disguises. He also had swapped out the license plate on his car, which would have made it harder to track him if he'd escaped.
The bloodshed comes three years after a heavily armed James Holmes burst into an Aurora, Colorado, showing of the Batman film "The Dark Knight Rises" and opened fire, killing 12 people
and injuring more than 70 others.
His story has been in the headlines recently, because of a Colorado jury's decision to convict him on murder charges
. The next step for the jurors is to decide whether he will be sentenced to death.
"It certainly is a coincidence that Colorado had that trial," Craft said. "We're looking at those similarities. We don't have any indication that he watched that or anything."
Time for recovery, mourning
The violence left the friends and families of two women grieving.
, 33, a Lafayette native who died at a hospital, operated the Red Arrow gift and toy shop in Lafayette. She played the ukulele and guitar for The Figs.
, 21, was killed at the scene. She was a student at Louisiana State University-Eunice and worked at the Coco Eros boutique. Her boyfriend of about three years, Matthew Rodriguez, was shot in the neck and armpit, according to his cousin.
Afterward, the movie's star, Amy Schumer, tweeted, "My heart is broken and all my thoughts and prayers are with everyone in Louisiana."