Orlando gunman made surveillance trips to Disney and Pulse nightclub
Authorities believe the gunman who killed 49 people at Orlando's Pulse nightclub conducted surveillance trips at both the club and Walt Disney World earlier this month, a law enforcement official said.
Omar Mir Seddique Mateen's visits happened between June 1 and June 6, said the official, who has knowledge of the investigation. The number of visits to each venue was not specified.
The dates coincided with Gay Days 2016 celebrations that were taking place at Disney World and other Orlando locations between May 31 and June 6.
Investigators believe the visits were intended to surveil the locations, based on information learned in interviews.
The visits also came in the same time period when Mateen was purchasing the weapons used Sunday morning's Pulse nightclub attack, which he picked up June 9 after a cooling-off period.
The day before that attack -- the deadliest mass shooting in U.S. history -- Mateen spent several hours at Disney Springs, the shopping and entertainment complex inside the Walt Disney World Resort, law enforcement officials said.
Authorities said they believe Mateen was alone at that time.
Prior Disney visit with wife
Disney security officials have told the FBI they believe another visit to Walt Disney World by Mateen on April 26 was to conduct reconnaissance. The FBI is investigating that possibility, the law enforcement official said.
Investigators don't know whether Mateen's wife, who was with him on the Disney World visit, knew or suspected at the time about her husband's intent, the official said.
Family items seized
The FBI has seized various documents from Mateen's home, as well as items the homes of his parents, sister and brother-in-law, the law enforcement official said.
The items included a Dell computer, a smartphone, a digital camera and related media.
Mateen's phone was recovered at Pulse. FBI Director James Comey would not say Tuesday whether they have accessed the phone.
To some, Mateen was angry and homophobic, spewing outrage at the sight of two gay men kissing.
But he was also a friendly and familiar face at the gay club he eventually terrorized, killing 49 people.
Investigators are trying to understand what spurred the New York-born security guard to commit the deadliest mass shooting in U.S. history.
Chris Callen, who worked at Pulse as a performer, told CNN's Anderson Cooper he'd seen Mateen dozens of times at the club. According to his estimate, Mateen visited Pulse twice a month over a period of three years.
"He was very friendly when we said 'hi.' He didn't seem like the kind of guy who just did what he did. It makes no sense," Callen said.
"My partner said that he was very nice [and seemed] comfortable.
Prior visits to Pulse are a line of inquiry investigators are pursuing, sources involved in the investigation tell CNN's Jim Scuitto and Evan Perez.
Pulse regular Kevin West told the Los Angeles Times that Mateen messaged him on a gay dating app several times in the year before the attack.
But that picture doesn't match up easily to the account of his coworkers who said Mateen was known to frequently spew anti-gay remarks.
"He was an angry person, violent in nature, and a bigot to almost every class of person," Dan Gilroy told CNN affiliate WPTV-TV in West Palm Beach. The former police officer asserts that he foresaw Mateen eventually committing an act of mass violence.
Mateen's ex-wife, Sitora Yusufiy, described a brief but violent relationship to a mentally-ill man whom she was only able to escape from through her family's help. She said he was physically abusive and a steroid abuser.
Mateen had even come to the attention of authorities, with the FBI interviewing him in two terror-related cases in recent years.
But both of the investigations were closed, and Mateen -- who would go on to call 911 and pledge allegiance to ISIS during his rampage -- was not under investigation or surveillance at the time of the attack.
The shooter's father, Seddique Mateen of Port St. Lucie, recalled an incident where his son reacted to a gay couple displaying affection.
He told CNN his son "had a reaction" when he saw the two men kissing in public, near women and children. The sighting "was surprising" to his son.
But the father didn't clarify further what kind of reaction his son had.
Gilroy, Mateen's former co-worker at PGA Village in Port St. Lucie, said Mateen often made homophobic, sexist and racist remarks.
"He would hit things and as he was hitting things, he would yell, and of course there was always curse words involved, and this wasn't seldom, this was all the time."
He said he asked his employers not to be assigned to work alongside Mateen, but this request was denied. At that point, Gilroy told Mateen he didn't want to continue their relationship on a personal level, according to WPTV.
"He acted very negatively toward that. He then started to text me 20 to 30 times a day. Call me 15 to 20 times," he said.
He said he wished he could have done something to prevent the tragedy.
"I saw it coming. I mean everything," he said. "He said he was going to kill a whole bunch of people."
FBI had investigated him twice
Mateen first came on the FBI's radar in 2013 when he made "inflammatory comments to co-workers alleging possible terrorist ties," Assistant Special Agent in Charge Ronald Hopper said. But investigators "were unable to verify the substance of his comments," he said.
In 2014, the FBI interviewed Mateen again over possible connections with Moner Mohammad Abu-Salha, a Florida man who became the first known American suicide bomber in Syria. The two men frequented the same mosque.
"We determined that contact was minimal and did not constitute a substantive relationship or threat at that time," Hopper said.
As a result, the mass killer was able to purchase a handgun and assault rifle legally in the days before the massacre, said Trevor Velino of the Bureau of Alcohol, Tobacco, Firearms and Explosives told reporters.
Mateen had tried to buy body armor, but the store where he tried to make the purchase didn't sell that product, according to a store manager.
''A hell of a lot of jihadist propaganda'
Comey, the FBI director, said that the agency is "highly confident" Mateen was radicalized, at least in part, by viewing extremism on the internet.
"There are strong indications of radicalization by this killer and of potential inspiration by foreign terrorist organizations," Comey said.
He said that investigators have found no indication the attack was directed from outside the United States or that Mateen was part of any kind of network.
According to one official, analysis of Mateen's electronic devices showed searches for jihadist propaganda, including videos of ISIS beheading.
"He consumed a hell of a lot of jihadist propaganda," the source said.
Married with a child
Mateen lived in a condo in Fort Pierce, Florida, with his second wife, a woman named Noor Salman, according to documents CNN obtained. He also had a son, 3½, according to Mateen's father.
He had worked for nine years as a security officer at G4S Secure Solutions, one of the world's largest private security companies.
According to a neighbor, he was a security guard at the St. Lucie County Courthouse, often manning the metal detectors at the front of the building.
Ex-wife: He abused me
His first wife, Yusufiy, painted a damning portrait of the killer, describing a physically abusive marriage to a man with anger issues.
Yusufiy, who is originally from Uzbekistan, said the relationship had started well after they met online about seven years ago.
"In the beginning, he was a normal being that cared about family, loved to joke, loved to have fun, but then a few months after we were married I saw his instability," she said.
"He would get mad out of nowhere. That's when I started worrying about my safety."
She said the abuse became a regular occurrence.
"He started abusing me physically, very often, and not allowing me to speak to my family, keeping me hostage from them," Yusufiy said.
"(My family) had to pull me out of his arms and find an emergency flight. ... I made a police report."
While her ex-husband was religious, she said, she did not believe his religion played a role in the attack, she said.
Father baffled by killings
Mateen's father, meanwhile, has said he's stunned by his son's actions and had no inkling that his son was about to commit an act of mass violence.
"I am as shocked as you are," he told CNN.
The killer was known to worship at the Fort Pierce Islamic Center.
In a separate interview, his father -- who had an occasional television show on an Afghan satellite channel in which he regularly criticized Afghanistan's government and Pakistan -- said he saw no religious motivation in the killing.
"Radicalism? No. He doesn't have a beard even. When someone becomes radical, they grow long beards and they wear clothes that you know, long clothes, and I don't think religion or Islam had nothing to do with this," he said.
He may have pledged allegiance to ISIS because "he wanted to boost himself," he said.