MIAMI -- Shortly after boarding an Orlando, Fla.-bound flight from Miami International Airport Wednesday, passengers on the plane said they saw a man get up from his seat and run down the aisle, with his screaming wife and a man in a Hawaiian shirt behind him.

"My husband! My husband!" one passenger said she heard the wife cry.

The chase ended moments later on the jetway, when authorities said he appeared to reach for his bag. The man in the Hawaiian shirt and another pursuer, both undercover federal air marshals, fired their guns.

The man, Rigoberto Alpizar, was shot and killed.

A Marshal Threat

Before he ran off the plane, Alpizar "uttered threatening words that included a sentence to the effect that he had a bomb," said James E. Bauer, special agent in charge of the air marshals field office in Miami.

Investigators closed Concourse D at MIA for about 30 minutes and spread passengers' bags on the tarmac. Dogs sniffed them for explosives, and bomb squad members blew up at least two bags. No bombs were found.

The remaining passengers on American Airlines Flight 924 were kept on the plane for an hour before being told to leave with their hands behind their backs, according to a passenger. They had to leave their possessions behind.

Federal officials later determined there was no link to terrorism.

Witnesses said his wife, Anne, frantically tried to explain that he was bipolar, a mental illness also known as manic-depression, and was off his medication.

Who Was Alpizar?

Early Thursday morning, Alpizar's wife arrived at her Maitland, Fla., home near Orlando with her mother and ran inside, unwilling to speak with a horde of reporters gathered outside.

News of the incident spread quickly to neighbors, many of whom said Alpizar, who went by the name of "Rigo," said he and his wife never seemed to cause any problems.

"They would play with the kids because they didn't have any kids, so they were friendly with all the kids in the neighborhood," said neighbor Sandie Benton. "They were a really nice couple."

Charles Baez, manager of a store in Orlando where Alpizar worked for 12 years until taking a job in the paint department at Home Depot, described him as a health enthusiast who biked and ran regularly and sometimes chided his co-workers when they ate fast food. Baez said Alpizar was always calm and patient with customers and that he never saw evidence of any mental problems.

Neither did his neighbors.

"I never saw him depressed," Dustin Benton said. "I never saw him doing his hyper-maniac stuff. He was just average. You know, he was just a normal guy."

Alpizar was returning from a missionary trip in Ecuador with his church, according to a neighbor who was watching his house.

The Alpizars had been married for about two decades and met when Anne was an exchange student in Costa Rica, family members said. Rigoberto moved to the United States 20 years ago and became a naturalized U.S. citizen.

His wife was a social worker who aided the mentally ill.

Authorities did not confirm Alpizar suffered from a mental illness.

Alpizar's brother-in-law told Local 10's Matt Lorch in a phone interview that Alpizar was a "good, good guy."

Air marshals and federal authorities are handling the investigation.