Deirdre Shesgreen and Kevin Johnson

USA TODAY

Family members of the 26-year-old suspect in the deadly shooting spree at a Florida airport say the Iraq war veteran recently complained of mental health problems, including hearing voices, and sought psychological help.

Two close relatives of the suspect, Esteban Santiago, suggested he had been hard hit psychologically by his military service overseas. Santiago's mother, who lives in Puerto Rico, said her son saw a bomb explode next to two of his friends in Iraq.

"Only thing I could tell you was when he came out of Iraq, he wasn't feeling too good," his uncle, Hernan Rivera, told The Record newspaper in New Jersey.

Esteban's brother in Puerto Rico, Bryan Santiago, said Saturday that he advised him to seek treatment but that his brother was only able to receive minimal assistance.

In August, Bryan said his brother began saying he was hearing voices. He told the Associated Press that Esteban's girlfriend in Alaska called his family in recent months to alert them to his mental state.

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The FBI said that in November, Santiago walked into an FBI office in Anchorage, saying the Islamic State terrorist group had gained control of his mind and was urging him to fight on its behalf.

"During the interview, Santiago appeared agitated and incoherent, and made disjointed statements,'' the FBI said in a statement Friday night. “Although Santiago stated that he did not wish to harm anyone, as a result of his erratic behavior, interviewing agents contacted local authorities who took custody of Santiago and transported him to a local medical facility for evaluation."

Two federal law enforcement officials said Saturday that Santiago was carrying a handgun when he arrived at the Anchorage office. The officials, who were not authorized to comment publicly, said the troubled 26-year-old went through standard security checks where the handgun was surrendered before he was directed to federal agents for questioning.

The Anchorage police chief gave a slightly different account, saying Santiago had ammunition and the gun was later retrieved from his vehicle.

The officials said it is not unusual in that rugged part of the country for people to be armed, and it didn’t raise unusual concern because the weapon was turned over during the required security check.

It was during the interview, however, that Santiago allegedly showed signs of erratic behavior and emotional distress when he claimed that U.S. intelligence agencies had gained control of his mind, urging him to align himself with the Islamic State terror group, the officials said.

As part of a threat assessment, agents reviewed criminal and counter-terrorism databases and interviewed the mother of his newborn child in Anchorage who indicated that Santiago did not intend to harm anyone. The FBI said it closed the assessment after conducting database reviews, interagency checks, and interviews of his family members.

The officials said he was then turned over to local police who were believed to have taken possession of the weapon that had been turned over at the security checkpoint. Police then referred Santiago for medical evaluation.

It wasn’t until Friday, the officials said, that Santiago surfaced again on the FBI’s radar following his arrest in connection with the mass shooting that left five dead.

"The FBI failed there. ... We're not talking about someone who emerged from anonymity to do something like this,'' Bryan Santiago told the AP, speaking in Spanish outside his family's house in Puerto Rico's southern coastal town of Penuelas. "The federal government already knew about this for months, they had been evaluating him for a while, but they didn't do anything.''

Although authorities were still scouring his communications for a specific motive beyond his emotional struggles, one of the officials said they believe the handgun used in the Friday attack was acquired legally.

Santiago, the official said, agreed to speak with investigators following his arrest, but at least some of his exchanges with investigators were incoherent. The official characterized the interview as a mixed bag of information, much of which would require corroboration

Esteban Santiago, who was born in New Jersey, moved to Puerto Rico when he was 2, his brother said. He grew up in Penuelas before joining the Puerto Rico National Guard in 2007.

He served in Iraq from April 23, 2010, to Feb. 19, 2011, a military spokeswoman said. Santiago's job was to clear roads of improvised explosive devices, and at least two members of his company were killed, Lt. Col. Candis Olmstead, director of public affairs for the Alaska National Guard, toldThe New York Times.

The suspect's military record lists him as a "combat engineer" whose postings also included Fort Dix, N.J., and Fort Leonard Wood, Mo. He received an Army Commendation Medal, Army Good Conduct Medal and a Combat Action Badge.

Santiago's aunt, Maria Luisa Ruiz of Union City, N.J., said in an interview on Friday that after Iraq, her nephew went back to live in Puerto Rico. He studied there, she said, but was unable to find work and decided to move to Alaska, where he joined the Alaska National Guard in 2014.

Olmstead described Santiago as a “traditional soldier” in the Headquarters & Headquarters Troop 297th Cavalry in Fairbanks, Alaska, but had received a general discharge from the military in August for “unsatisfactory performance,” said Olmstead. She did not elaborate on the circumstances of his discharge.

Ruiz said Friday that her nephew found work in security in Alaska and seemed happy after the birth of his son in September. She showed reporters a photo of him at a hospital holding his newborn son. His dark hair is closely cropped, and he’s wearing a T-shirt from the band Disturbed.

But, says Ruiz, his demeanor changed about a month ago. “It was like he lost his mind,” she said in Spanish. “He said he saw things.”

She said Santiago recently was hospitalized for two weeks after suffering from an unspecified condition. “I don’t know why this happened,” she told reporters at her home on Friday before FBI agents arrived and authorities closed off the street.

“Right now, my family and I are suffering," she said. "My family and I are in shock right now. We don't know what is going to happen. It's sad but we have to confront the situation. … This hurts me as if he was my own son. I hope God is with him.”

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Senator-elect Nelson Cruz, a friend of the family who represents the town in Puerto Rico where they live, said he had been talking regularly with Bryan Santiago since the shooting.

"They're very humble and very Christian people," Cruz said of Esteban's brother and mother. "They want to tell the families of the victims that they're extremely saddened and extremely upset by what happened."

Contributing: The Associated Press; Kevin Johnson and Tom Vanden Brook, in Washington; Keldy Ortiz and Abbott Koloff , The (Bergen County, N.J.) Record.