FBI Director James B. Comey on Monday said the man who killed 49 people in an LGBT nightclub in Orlando, Florida, was clearly “radicalized” and defended the bureau’s work investigating 29-year-old Omar Mateen, saying he does not think agents should have done anything differently.
During a briefing at FBI headquarters, Mr. Comey described his agency’s first contact with Mateen, who died in a gunbattle with police Sunday. He said a 10-month preliminary investigation was triggered when Mateen told co-workers at a private security firm that he had family connections to al Qaeda and had mutual acquaintances with Tamerlan and Dzhokhar Tsarnaev, the Boston Marathon bombers.
The investigation, initially authorized for six months and later extended for an additional four months, included use of confidential sources who engaged Mateen, though Mr. Comey declined to describe their specific interactions. FBI investigators did interview Mateen and reviewed his communications and travel he made to Saudi Arabia several years prior.
Mr. Comey said Mateen admitted to making the statements to co-workers but said he did so “in anger, because he thought his co-workers were discriminating against him and teasing him because he was Muslim.”
Mateen was placed on a watch list. Mr. Comey declined to specify whether it was a no-fly list or the Terrorist Screening Database.
During the 10 months the investigation was active in 2013, the FBI would have been notified if Mateen had sought to purchase a firearm, said Deputy Attorney General Sally Yates.
But Mateen was removed from the watch list shortly after the closure of the investigation, so his legal purchase this month of two firearms raised no alarms. The owner of the gun store said Mateen passed a full background check in June.
“Certainly in retrospect in this case, we would have liked to have known about it,” Ms. Yates said Monday of the firearms purchase.
Asked whether she thought policy should be changed to allow flagging of suspects who purchase firearms after they have been dropped from watch lists, Ms. Yates said it was a determination that would take a “longer and more thoughtful look.”
Several months after the closure of the investigation in March 2014, Mateen was on the FBI’s radar again — this time after his name was brought up as law enforcement officials investigated a suicide bomber from Florida and officials learned that Mateen had attended the same mosque as the bomber.
“Our investigation turned up no ties of any consequence between the two of them,” Mr. Comey said.
As part of the 2014 probe, which Mr. Comey said did not amount to a formal investigation of Mateen, agents were told by someone who knew Mateen that they had concerns about him radicalizing.
They said he had watched Anwar al-Awlaki videos. But the person told investigators that Mateen had since married and had a child and he no longer considered Mateen a possible threat.
Questions about Mateen’s motive were also being fueled by other factors Monday night, from his family background to reports that he’d been a regular at the Pulse nightclub in Orlando, as well as possibly other gay clubs, and that he’d used gay dating apps.
The Orlando Sentinel reported that at least four regulars at the gay nightclub where the massacre took place claimed to have seen Mateen there on multiple previous occasions.
“Sometimes he would go over in the corner and sit and drink by himself, and other times he would get so drunk he was loud and belligerent,” Ty Smith told the newspaper, adding that he’d seen Mateen there at least a dozen times.
Kevin West, another regular, told the Los Angeles Times that Mateen messaged him on and off for a year before the shooting using the gay chat and dating app Jack’d, but that they’d never met until early Sunday morning, when Mr. West says he noticed Mateen — whom he knew by sight but not by name — outside the club about an hour before the shooting.
Investigators are looking into Mateen’s ideological alignments and actions ahead of the deadly attack, which also wounded 53 others.
The gunman, who wielded an AR-15 semi-automatic rifle and a handgun, spoke with a 911 three times while holed up inside the nightclub with hostages, pledging allegiance to the leader of the Islamic State.
But he also “appeared to claim solidarity” with the brothers who bombed the Boston Marathon — referring them as his “homeboys” — and a suicide bomber who acted on behalf of the Nusra Front, a group at odds with the Islamic State, officials said. The contradictory allegiances seemed to indicate that Mateen was not officially aligned with any one terrorist group and muddled his motive for the attack.
“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,” Mr. Comey said, adding that investigators are still working to understand the role that bigotry may have played in motivating the attack on the LGBT nightclub.
At the White House, President Obama called the attack an apparent example of “homegrown extremism.”
More details of the bloodbath emerged. Orlando Police Chief John Mina said Mateen was “cool and calm” during phone calls with police negotiators. The chief said he sent in the SWAT team to bash through a wall after Mateen holed up with hostages in a bathroom and began to talk about bombs and an explosives vest.
“We knew there would be an imminent loss of life,” Chief Mina said. As it turned out, Mateen had no explosives with him.
Five of the wounded were reported in grave condition, meaning the death toll could rise. A call went out for blood donations.
People familiar with terrorism investigations say the bar for earning a spot on the FBI’s watch list is low, which can pose a problem for investigators.
“The standard for inclusion on the main watch list is a very, very loose one,” said Hina Shamsi, director of the American Civil Liberties Union’s National Security Project.
Low barriers can lead to less-thorough investigations by overburdened agents who are forced to monitor too many suspects, said Michael German, a former FBI agent and Brennan Center for Justice fellow.
“A big part of the problem is because they have lowered the threshold to conduct these investigations, the vast majority of which are false positives, it’s response in these investigations oftentimes aren’t as thorough as they need to be,” Mr. German said.
But he cautioned that FBI agents “are not given a crystal ball to go along with their badge and gun.”
“They can’t be expected to predict the future,” he said.
In Orlando, mourners piled bouquets around a makeshift memorial, and people broke down in tears and held their hands to their faces while passing through the growing collection of flowers, candles and signs about a mile from the site of the massacre.
About 300 employees of the Red Lobster restaurant chain — some in business suits, some in chefs’ uniforms — emerged from the company’s corporate headquarters and walked two-by-two across the street to the memorial, each carrying a red or white carnation.
“We will not be defined by the act of a cowardly hater,” vowed Mayor Buddy Dyer, whose city of a quarter-million people is known around the globe as the home of Walt Disney World and other theme parks.
The tragedy hit the city’s gay and Hispanic communities especially hard. It was Latino Night at the club when the attack occurred.
“As the names come out, they are overwhelmingly Latino and Hispanic names,” said Christina Hernandez, a Hispanic activist. “These were not just victims of the LBGT community, but of the Hispanic community as well. This was senseless bloodshed.”
Counterterrorism analysts have been warning for years about the dangers of “lone wolf” attackers who act in sympathy with extremist groups such as the Islamic State but are not directed by them.
Mateen’s father, Seddique Mir Mateen, told reporters that the massacre was “the act of a terrorist” and added: “I apologize for what my son did. I am as sad and mad as you guys are.”
He wouldn’t go into details about any religious or political views his son held, saying he didn’t know. Asked whether he missed his son, he said: “I don’t miss anything about him. What he did was against humanity.”
Mr. Comey vowed to take a hard look at the FBI’s work and what it should have done differently.
“So far, the honest answer is, I don’t think so,” Mr. Comey said.
• Guy Taylor contributed to this article, which is based in part on wire vice reports.