The director of the FBI, James Comey, said Monday that the man who carried out the worst shooting in US history at a gay nightclub in Orlando mentioned links to Al Qaeda, Hezbollah, and the Islamic State - all within a three-year span.
"We first became aware of him in 2013, while he was working as a security guard at a local courthouse," Comey told reporters Monday. "He made inflammatory and contradictory statements about terrorism that raised concern with his coworkers, and claimed family connections to Al Qaeda."
He continued: "He then said he was a member of Hezbollah, which is a Shiite terrorist organization that is ideologically opposed to Al Qaeda, a Sunni terrorist organization."
Law-enforcement officials have identified the shooter as 29-year-old Omar Mateen. Comey said he was declining to use his name. Comey said the FBI's Miami office opened up a preliminary investigation into the shooter in 2013 that lasted 10 months.
"We interviewed him twice, and he admitted to making statements about the terrorist organizations," Comey said. "But he said he did it in anger because he thought his coworkers were discriminating against him."
The FBI's second investigation into Mateen "came about in an indirect way" in 2014, Comey said. The FBI's Miami office was investigating a Florida man who had blown himself up on behalf of Al Qaeda in Syria - an organization known as Jabhat al-Nusra. The office discovered he had attended the same mosque as Mateen, the Islamic Center of Fort Pierce.
The FBI had kept confidential sources connected to the killer and tracked him since opening the investigation in 2013. According to one source, Comey said, Mateen had mentioned the videos of the extremist Islamic preacher Anwar al-Awlaki, who was linked to Al Qaeda.
But the source told the FBI that when Mateen later got married, had a child, and became employed, he was no longer concerned about his allusions to radical Islam.
Ultimately, the FBI determined that there were " no ties of any consequence" between Mateen and the suicide bomber, Moner Abu-Salha. On Sunday morning, however, Mateen called 911 during his rampage and told the dispatcher that Abu-Salha had partly inspired him to carry out the attack on Pulse nightclub.
Comey confirmed that the 911 call itself painted a bizarre picture of where Mateen's loyalties lay.
"During his call to 911 he said he was doing this for the leader of ISIL, who he claimed allegiance to," Comey said. "But he also mentioned the Boston Marathon bombers, who were inspired by Al Qaeda, and Abu-Salha, who blew himself up for al Nusra."
Comey noted that Nusra and ISIS are fighting each other in Syria.
"There is no indication he was part of a plot from outside the US, and no indication of what group he supported," Comey said, noting that he demonstrated a "general support for radical Islamist groups."
"There is confusion about his motives," Comey said.
In a press conference Monday, Orlando police said they spoke with Mateen at least three times over the course of several hours on Sunday morning. Orlando Police Chief John Mina said Mateen appeared "cool and calm" during negotiations throughout the attack.
"He really wasn't asking for a whole lot. We were doing most of the asking," Mina said. "Our negotiators were talking with him, and there were no shots at that time, but there was talk about bomb vests and explosives. There was an allegiance to the Islamic State."
A witness who pretended to be dead in the Pulse nightclub bathroom and overheard Mateen's phone conversation with police before they stormed the club said Mateen demanded that the US "stop killing ISIS." Mateen presumably was referring to the US-led air campaign against ISIS targets in Syria and Iraq.
The ISIS-affiliated news agency Amaq News broadcast a claim of responsibility from ISIS for Mateen's rampage, shortly after the news broke that Mateen had pledged allegiance to ISIS in the 911 call.
The agency said the shooting was the work of "an ISIS fighter," multiple media outlets have reported. ISIS affiliates released another statement on an ISIS-linked radio station Monday morning claiming responsibility for the attack.
The overnight shooting at Pulse nightclub - a gay club in central Orlando - is the deadliest shooting in US history, with more fatalities than the mass shooting at Virginia Tech in 2007 (32 dead) and the mass shooting at Sandy Hook Elementary School in Newtown, Connecticut, in 2012 (27 dead).
Mateen, a US citizen, was born in New York in 1986 to two Afghan immigrants. An FBI representative said he "was organized and well-prepared" for the attack, renting a car to drive from Fort Pierce to Orlando armed with an AR-15 and a handgun that he had legally purchased a few days prior.
Mateen was a security guard and had a Florida firearms license that allowed him to carry concealed weapons.