Updated

The 26-year-old who authorities said opened fire last week inside a Ft. Lauderdale airport reportedly cancelled his flight reservation for a trip to New York on New Year’s Eve, ABC News reported, citing authorities.

The report said Esteban Santiago may have been deterred due to the NYPD presence during celebrations. The report did not explain why he ended up purchasing a $278 ticket to Florida.

Santiago, an Iraq war veteran from Anchorage, is facing federal charges that could result in a death sentence.

A few reported details suggest Santiago was troubled. His mother said he had been deeply shaken by seeing a bomb explode next to two friends while serving in Iraq in 2010, and relatives said he seemed different when he returned from service.

Santiago's brother Bryan said Esteban told him last August that he was hearing voices and felt he was being chased. In November, he walked into an FBI field office in Alaska and said the federal government was controlling his mind and forcing him to watch Islamic State videos, authorities said.

perpwalk

Esteban Santiago is taken from the Broward County main jail as he is transported to the federal courthouse in Fort Lauderdale (Amy Beth Bennett/South Florida Sun-Sentinel via AP)

At that point, officials seized his handgun and had him formally evaluated. After four days he was released and his gun was returned.

But none of these details, by themselves or even together, are enough to draw conclusions, experts say.

Plenty of people have had such experiences in their past and don't commit mass murder, said criminologist James Alan Fox, of Northereastern University. The fact that Santiago was released after the evaluation indicates authorities believed he was not dangerous to himself or others, Fox said.

"There's a difference between being psychotic and being dangerous and psychotic," Fox said.

The Assocated Press contibuted to this report