ORLANDO (CBSNewYork/AP) — The Orlando nightclub gunman enrolled in an online website for lessons on Islam that was run by an imam who openly preached against the gay community, sources said.

A law enforcement source told CBS News that Omar Mateen, who killed 49 people at the gay nightclub Pulse, enrolled online in Fundamental Islamic Knowledge Seminary.

The source explained to CBS News it was operated by Abu Taubah, also known as Marcos Robertson, an imam who preached anti-gay rhetoric.

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The source also confirmed that Mateen searched the Pulse nightclub online.

Investigators have confiscated tapes from surveillance cameras in the nightclub’s neighborhood, including from ATMs, and are combing through them as part of the investigation into Mateen and whether he had been in the area prior to the shooting, as well as other information they may get from the tapes.

Mateen pledged allegiance to the Islamic State of Iraq and Syria on a 911 call during the shooting. ISIS has claimed responsibility for the attack and the terror group’s radio hailed the attack and called Mateen “one of the soldiers of the caliphate in America.” But it gave no indication the group planned or knew of the attack beforehand.

“So far, we see no indication that this was a plot directed from outside the United States, and we see no indication that he was part of any kind of network,” said FBI Director James Comey. But he said Mateen was clearly “radicalized,” at least in part via the internet.

Comey said the bureau is also trying to determine whether Mateen had recently scouted Disney World as a potential target, as reported by People.com, which cited an unidentified federal law enforcement source.

“We’re still working through that,” Comey said.

The FBI chief defended the bureau’s handling of Mateen during two previous investigations into his apparent terrorist sympathies. As for whether the FBI should have done anything differently, “so far the honest answer is, ‘I don’t think so,'” Comey said.

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