Authorities: Fort Lauderdale Suspect First Planned New Year’s Eve Trip to New York

Santiago bought his one-way, $278 ticket last Tuesday, authorities say.

— -- Esteban Santiago’s initial destination may not have been Fort Lauderdale but New York City, where he had made a reservation to fly in on New Year’s Eve, authorities told ABC News.

But for some unknown reason, he canceled the flight and a few days later booked a one-way $278 ticket to Florida.

New York City counterterrorism officials are investigating Santiago’s plan to visit the city and whether he planned to stay in New York or transfer to another flight.

On Friday — as surveillance video obtained by TMZ shows — Santiago arrived in the Fort Lauderdale airport in Florida and 43 minutes later pulled a 9 mm handgun from his waistband and began firing off found after round.

Police said that he emptied his first magazine of bullets and reloaded so that he could keep shooting.

After 34 seconds of terror, five people were killed, and six more were injured in a scene of mayhem that the shooter’s friends and family say could have been prevented.

The death of his father made matters worse, she said.

“He wasn’t the same after he came from Iraq and after his father,” she said. “There was something in his voice that wasn’t right. He needed to tell somebody something. He couldn’t. He just didn’t dare to.”

She said that they sought help for him from the Department of Veterans Affairs.

“We had let Veterans [Affairs] know that he was having some mental problems, that he wasn’t feeling all right, and they did nothing,” she said. “They didn’t do anything.”

Repeated calls by ABC News on Monday to the VA Caribbean Healthcare System in San Juan, Puerto Rico, went unanswered.

On Jan. 10, 2016, he was arrested after breaking down a door in his residence and trying to strangle a different girlfriend. Instead of a jail time, he was required to attend anger management courses, the records show.

During that incident, Santiago “appeared agitated, incoherent and made disjointed statements” but “stated he did not wish to harm anyone,” Ritzman said.

But after a brief hospitalization for a mental examination, Santiago was released and on Dec. 8 was allowed to collect his handgun, which law enforcement had confiscated.

In an interview in Penuelas, Puerto Rico, with ABC News on Saturday, the shooter’s brother, Bryan Santiago, was critical of the FBI.

“When he went to the FBI, he was unconsciously asking for help,” the brother said.

“How is it possible that they only hospitalized him for four days?” he wondered. “The mistake was theirs, and what I criticize is that the federal government knew about his situation for months.”

“How is it possible that the federal government let him keep his gun?” he said. “All this could have been avoided.”

With Esteban Santiago detained in Florida, authorities are investigating his claims — real or imagined — that he had been in contact with the ISIS terrorist group online.

Since the attack, investigators recovered his computer from a pawn shop, and the FBI is examining it to determine whether the alleged shooter created a jihadist identity for himself using the name Aashiq Hammad, according to officials familiar with the case.

What they’re asking is, is there a connection with a terrorist organization?’” he explained. “What they should be asking is, ‘Does this person I’m interested in present a risk of committing an act of violence?’”

“Based on the attacks we’ve seen in this country, these aren’t traditional terrorists we’re dealing with. We’re dealing with people who have underlying mental health issues, who are self-connecting with extremist causes and are murdering people in furtherance of some perceived grievance,” he said.

As authorities work to piece together Santiago’s motive, there will also be introspection as agents ask themselves what, if anything, they could have done to prevent this tragedy.

ABC News’ Paul Blake wrote this story, and Alex Hosenball and Randy Kreider contributed from New York.

ABC News’ Alyssa Pone contributed from Anchorage, and Sabina Ghebremedhin and Shahriar Rahmanzadeh contributed from Los Angeles. Bellido, a freelance journalist for ABC News, contributed from Penuelas.

This story was originally published on Monday morning. It has been updated throughout the day as new information has become available.