20160618_wesat_orlando_shooter_update_few_warning_signs_pointed_to_radicalization.mp3

As investigators probe the background of Omar Mateen, whose attack on Pulse nightclub in Orlando left 49 people dead, they say he bore few warning signs of radicalization.

Mateen had allegedly pledged allegiance to ISIS in a 911 call during the attack, as The Two-Way has reported. But as further details emerge about the shooter, investigators say Mateen's profile is more like that of a "typical mass shooter" than an individual radicalized by ISIS, as NPR's Dina Temple-Raston reports.

In fact, intelligence officials and investigators say they're "becoming increasingly convinced that the motive for this attack had very little — or maybe nothing — to do with ISIS."

Speaking on Weekend Edition Saturday, Dina says that al-Qaida and ISIS-inspired attacks tend to follow a different pattern. She explains:

"We know that during the attack the gunman posted messages on Facebook saying he was doing this on behalf of ISIS. But officials have yet to find any of the precursors usually associated with radicalization. They've interviewed dozens of people who either knew him or had contact with Mateen."And they say that they've yet to find any indication that he became noticeably more religious, which is one of the indicators of radicalization. He still was going to the same mosque. The way he dressed didn't change. His relationship with his family didn't change in any way. And these are all typically warning signs that parents and friends and educators are told to look for if they're worried that someone they're close to is radicalizing."

She adds "this isn't science," but so far the signs of radicalization aren't there, which has led investigators to wonder whether the 29-year-old invoked the name of ISIS to garner more publicity for his deadly attack.

The assault resulted in a hostage situation, and Mateen was ultimately killed in a firefight with law enforcement officers.

Investigators have also been struck by "how closely Mateen's biography adheres to profiles that they associate with typical mass shooters," Dina adds:

"He was bullied as a kid in school. He had well-documented behavioral problems. He was aggressive toward other kids. As he got older, things didn't get much better. He took steroids, he jumped from job to job, he had a history of domestic violence. And all these things together fit into a mass shooter's profile."

Dina says Mateen reportedly beat both his first wife and his second one — and "violence and control and power are often precursors to mass attacks."

You can find our earlier coverage of details that have emerged on Mateen here.

As we reported, Mateen, who was born in New York City, had been interviewed three times by the FBI in two separate investigations — one regarding inflammatory comments to co-workers and another regarding possible links to Moner Mohammad Abu Salha, a U.S. citizen who blew himself up in Syria. Both investigations were closed.

Global security company G4S said Mateen had worked for them since 2007. Authorities say he purchased the two firearms he used in the attack legally.

Citing reports that Mateen may have spent time at the Pulse nightclub, which is frequented by gays and lesbians, and used gay dating apps, Dina adds that investigators are beginning to lean towards a particular narrative: "Mateen may have had some problems with his sexuality, maybe even had some latent attraction to men. And he lashed out at the gay community as a result."

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