The hours-long standoff began around 12:30 p.m. Tuesday when a gunman - identified by police as 20-year-old Fuaed Abdo Ahmed - took two women and a man captive at Tensas State Bank branch in St. Joseph, which sits near Louisiana's border with Mississippi.
During hostage negotiations, authorities were able to get Ahmed on the phone with a friend in Alaska, Louisiana State Police superintendent Col. Mike Edmonson said. That was crucial in convincing Ahmed to eventually release a female hostage.
Ahmed had written a letter "detailing exactly what he was going to do," Edmonson said.
"He was mad at people that he said were mean to him," he said. "He had voices in his head."
Edmonson said the man grew increasingly erratic as negotiations went on, sometimes hanging up on police. One of his demands to authorities was that they get the device out of his head, Edmonson said.
Eventually, Ahmed told negotiators he was going to kill the two remaining hostages. Edmonson said state police entered the building just before midnight Tuesday.
That's when Ahmed shot the two hostages and then police shot and killed him, Edmonson said. Edmonson said both hostages were shot in the upper body. The second hostage who was shot was taken to a hospital in critical condition, but Edmonson said he did not have any other information on them.
The hostages were both shot with a handgun, but Edmonson said Ahmed was also armed with a rifle. He also had a duffel bag containing items he was going to use to torture the hostages.
"His intent was to inflict pain and kill these individuals," Edmunson said.
But Edmonson said there was no indication Ahmed had any history with the hostages, who were bank employees, and authorities did not know why he picked the bank. The bank sits across the street from a service station owned by Ahmed's family.
"These were good, God-fearing people," he said of the hostages.
Edmonson said Ahmed's parents were from Yemen, but he was a U.S. citizen and there was no indication that he had a political or religious motive.
On a Facebook page under Ahmed's name that was set up in the spring, Ahmed describes himself as a native of Fresno, Calif. On the page, he is seen in photos smiling and wearing a baseball cap backward, and with friends.
Ahmed discusses philosophy of life from the Tao Te Ching, a 6th century BC Chinese text, and is a fan of comedian Jerry Seinfield, rapper Eminem and Islam. He makes no specific references to political or religious extremism.
But recent posts show a darker side.
In a post on Sunday, he displays a cartoon strip that focuses on an apparent hostage situation. In it, a gunman points a pistol at a hostage. "I'll release the hostage if you give me a sandwich!" says the gunman in the strip.
Negotiators in the next frame then talk about the demand, with one asking "How close is the nearest deli?" ''Three blocks," the second man replies.
"Okay, you can kill the hostage," one negotiator calls back to the hostage-taker.
Ahmed's final post, made Tuesday just hours before the hostage standoff began, is of a photo of a man with a sword attacking a tank. Under the photo is a quote from the novel "If This Goes On," a 1940 science-fiction novel by Robert Heinlein that speculates on life in a futuristic American theocratic Christian society.