ORLANDO, Fla. – Orlando mourned the 49 people slaughtered in the attack on a gay nightclub, as the White House and the FBI portrayed the killer Monday as an apparent "homegrown extremist" who espoused support for a jumble of often-conflicting Islamic organizations.
The last of the bodies were removed from the nightclub late Sunday, and vigils and makeshift memorials to the victims of the deadliest mass shooting in modern U.S. history began to take shape as counterterrorism authorities delved into gunman Omar Mateen's background and defended their handling of their previous contacts with him.
Wielding an AR-15 semi-automatic rifle and a handgun, Mateen, a 29-year-old American-born Muslim, opened fire at the crowded Pulse Orlando club early Sunday. He was killed in a gun battle with a SWAT team after police used explosives and a small armored vehicle to punch a hole in a wall and allow dozens of club-goers to escape, police said.
The tragedy shocked the nation and cast a pall over Orlando, known all around the globe as the home of Walt Disney World and other theme parks.
"We will not be defined by the act of a cowardly hater," Mayor Buddy Dyer vowed.
FBI Director James Comey said that Mateen had "strong indications of radicalization" and was probably inspired by foreign terrorist organizations.
He said Mateen called 911 around the time of the attack and not only pledged loyalty to the Islamic State but also expressed solidarity with the Tsarnaev brothers, who carried out the Boston Marathon bombing, and a suicide bomber who died on behalf of the al-Nusra front, a group at odds with the Islamic State.
In the past few years, Mateen also expressed support for both al-Qaida and its enemy Hezbollah, Comey noted.
The FBI investigated Mateen for 10 months beginning in May 2013 after he was said to have made inflammatory remarks in support of terrorists.
"He said he hoped that law enforcement would raid his apartment and assault his wife and child so that he could murder himself," Comey said. "When this was reported to us, the FBI's Miami office opened a preliminary investigation."
Comey said investigators introduced him to confidential sources, followed him and reviewed some of his communications, but Mateen claimed he made the remarks in anger because co-workers were teasing and discriminating against him because he was Muslim. The investigation was brought to a close.
"So far, the honest answer is, 'I don't think so,'" Comey said when asked whether the FBI should have done anything differently.
At the White House, President Barack Obama said there is no clear evidence so far that Mateen was directed by the Islamic State. He said Mateen was inspired by radical information over the internet, calling it another apparent example of "homegrown extremism."
Meanwhile, a steady stream of people filed through a makeshift memorial about a mile from nightclub. It consisted of dozens of bouquets and candles.
Just after noon about 300 employees of Red Lobster -- some in business suits, some in chef uniforms -- paraded, walking two-by-two across the street to a park, each carrying a red or white carnation.
Counterterrorism experts have been warning in the past few years about the danger of so-called lone wolf attackers who act in sympathy with extremist groups like the Islamic State but are not directed by them.
Despite the 911 call from the club, Mateen's intentions seemed to become murkier when his Afghan immigrant father suggested another motive: anti-gay hatred. The father said his son got angry a few months ago when he saw two men kissing in Miami.
Also, Mateen's ex-wife attributed the violence to mental illness, saying he was bipolar and abusive toward her.
"This was a sick person that was really confused and crazy," Sitora Yusifiy said.
Obama said investigators are still looking into the killer's motivations and considering all possibilities, noting that Muslim extremist groups like the Islamic State have been known to target gays.
The Islamic State's radio called Mateen "one of the soldiers of the caliphate in America." Al-Bayan Radio, a media outlet for the extremist group, hailed the attack, saying that it targeted a gathering of Christians and gays and that it was the worst attack on U.S. soil since 9/11.
The statement gave no indication of whether the group planned or knew of the attack beforehand.
As a security guard for London-based G4S, Mateen was assigned to work the guardhouse at PGA Village in Port St. Lucie.
"Omar Mateen was employed by G4S at a residential community in South Florida and was off-duty at the time of the incident," a statement from the security company said. "Mateen was subject to detailed company screening when he was recruited in 2007 and re-screened in 2013 with no adverse findings. He was also subject to checks by a U.S. law enforcement agency with no findings reported to G4S."
Mateen had also worked security at the St. Lucie County courthouse, where attorney Steven Smith remembered him.
"I just remember, kind of, a cold stare," Smith said.
"Do you remember that in hindsight or did you notice that then?" Local 10 News reporter Glenna Milberg asked.
"I remember that in hindsight," Smith said.
Mateen's father, Seddique Mateen, told Milberg that he wishes his son had never been licensed to carry weapons.
"I'm against his action," he said. "It was anti-humanity and anti-family, because America is his family."
Seddique Mateen said his son resisted his advice to try to do better in life.
"I don't agree with him and I don't forgive him," he said.
Thirty-nine of the dead were killed at the club, and the others died at hospitals, the mayor said. Authorities were still notifying victims' families Monday.
At least 53 people were hospitalized, including five in grave condition, meaning the death toll could rise.
The previous deadliest mass shooting in modern U.S. history was the 2007 attack at Virginia Tech, where a student killed 32 people and took his own life.
Ed Henson, owner of the St. Lucie Shooting Center, where Mateen recently legally purchased two of the guns used in the shooting, spoke to reporters Monday.
"An evil person came in here and they legally purchased two firearms from us, and if he hadn't purchased them from us, I'm sure he would have gotten them from another local gun store in the area," Henson said.
Mateen exchanged gunfire with 14 police officers at the club and took hostages at one point. In addition to the assault rifle and handgun, he had a weapon in his vehicle, police said.
Police Chief John Mina said officers held back for some time because Mateen indicated he had a bomb vest. About 5 a.m., authorities sent in a SWAT team to rescue the remaining club-goers, Mina said.