LAFAYETTE, La. - (CNN) -- As moviegoers settled in for the comedy "Trainwreck," John Russell Houser stood up and unloaded at least 13 shots. Then, as people rushed from the theater, the 59-year-old man joined them and headed outside, apparently toward his blue 1995 Lincoln Continental.
Then Houser noticed the sirens from police converging on the Lafayette, Louisiana, theater. So he went back inside and took his own life.
By that point Thursday night, 21-year-old Mayci Breaux of Franklin, Louisiana, was dead. Ten others were wounded, including 33-year-old Lafayette resident Jillian Johnson, who would die at a nearby hospital.
And a city, state and country were searching for answers.
"Why did he come here? Why did he do (this)?" Col. Michael Edmonson of the Louisiana State Police said Friday morning. "We don't know that."
Police: 'He could have come out and done additional harm'
Houser was a drifter who'd become estranged from his family back home in Louisiana and arrived in Lafayette, a city of about 120,000 people about 60 miles west of Baton Rouge, in early July. He was staying at a Motel 6, about 4 miles north of his eventual target, the Grand 16 theater.
Why he'd gone there is a mystery. Lafayette Police Chief Jim Craft said Houser once had an uncle who lived in the city, but he'd died about 35 years ago. Authorities gave no indication that he knew anyone else there.
But they have some clues suggesting this wasn't a spontaneous act. Houser's hotel room had wigs, glasses and other apparent disguises. And he'd swapped out the license plates on his Lincoln Continental, parking it right outside an exit door to the Grand 16.
Yet, while he paused his barrage of bullets to head toward the exits, he never made it to the car.
Two police officers who happened to be at the theater made their way toward where "Trainwreck" was playing, as patrons rushed away from the carnage and their law enforcement colleagues on the outside rushed to get there.
"They heard a shot," Craft said. "And upon entering the theater, the suspect was found deceased from a self-inflicted gunshot wound."
Edmonson said that the gunman got outside, saw police coming, and then returned to kill himself.
"He could have come out and done additional harm," the state police colonel said. "... It was an ordinary moment, an ordinary night, and it turned into an extraordinary situation."
Pops, muzzle flashes and panic
The shooting victims are in area hospitals, except for two who have been released. One of the ones still hospitalized was in critical condition Friday morning, Craft said.
As they recover, others are thankful they're not hurt physically even as they try to make sense of why someone would fire at least 13 bullets into a movie theater packed with about 100 people, none of whom he apparently knew.
Randall Mann, an executive at Acadian Ambulance, which responded within 6 minutes, said his 21-year-old daughter -- who was watching "Trainwreck" from the second-to-last row, the same one as Houser -- is "very traumatized" but unharmed.
"She made a comment that she was just thankful that the shooter did not pick one of the theaters that had some children's movies in it because she would have hated for the children to have witnessed that," he told CNN. "I took that as a great first step of her eventually coping with this."
He said that when his daughter heard the first pops, she thought 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 then ran for her life, joining a swarm of 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.
Louisiana Gov. Bobby Jindal recounted 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.
This all unfolded around 7:30 p.m. (8:30 p.m. ET), about 20 minutes into a film that Houser had bought a ticket for just like everyone else. Afterward, the movie's star Amy Schumer tweeted, "My heart is broken and all my thoughts and prayers are with everyone in Louisiana."
"Obviously the audience was laughing, maybe that made him angry," Mann speculated. "I don't know. But why did he pick that movie? It's just very strange."
Days after guilty verdict in Aurora shooting case
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 over 70 more.
His story has been very much in the headlines recently, given a Colorado jury's decision to convict him on murder charges. The next step for the jurors is to decide whether he is sentenced to death.
Security measures were stepped up at some cinemas after the Aurora shooting. Still, theaters across the United States fundamentally remain freewheeling places, where ticket holders can wander in and out, unbothered by the intense security measures that now typify airports and public buildings. Ticket sales also didn't slump.
Did that eerily similar episode factor, in any way, to what happened about 1,200 miles away in Lafayette? Authorities haven't said.
So far, they don't have much to go on. Houser had a criminal history, but it dates back to a possible arson and case of giving alcohol to a minor that's at least 10 years old. There are indications that alcohol may have been consumed, but there are no indications of drug use, said Craft, the Lafayette police chief.
As investigators try to figure that out, Edmonson, the Louisiana State Police colonel, urged people to keep in mind the "two beautiful lives" Houser took.
"Don't lose sight of the fact that these two individuals had a vision, had a name, had a future," he said. "It wasn't to die as they did horribly in this theater here."
CNN's Brian Stelter, Ed Payne, Ralph Ellis, Kevin Conlon, Sam Stringer and Tony Marco contributed to this report.