Orlando gunman Omar Mateen identified himself as an Islamic soldier in calls with authorities during his rampage and warned a crisis negotiator that in coming days "you're going to see more of this type of action going on," according to transcripts released by the FBI on Monday.
The partial transcripts were of a 911 call made by Mateen and three conversations he had with the police crisis negotiators during the worst mass shooting in modern U.S. history, in which 49 people died and dozens were wounded.
Those communications, along with Facebook posts and searches Mateen made around the time of the shootings, add to the public understanding of the final hours of Mateen's life and to the possible motivations behind the rampage.
The first call came more than a half-hour after shots rang out, when Mateen told a 911 operator, "Praise be to God, and prayers as well as peace be upon the prophet of God," he told the dispatcher, referring to God in Arabic.
"I let you know, I'm in Orlando and I did the shootings."
During the 50-second call with a dispatcher, Mateen "made murderous statements in a "chilling, calm and deliberate manner," Ronald Hopper, FBI assistant special agent in charge in Orlando, said during a news conference.
However, there is no evidence Mateen was directed by a foreign terrorist group, and he was radicalized domestically and on his own, Hopper said.
Mateen's name and the groups and people to whom he pledged allegiance were initially omitted from the excerpt. But the Justice Department reversed course later Monday, providing a more complete transcript confirming Mateen pledged allegiance to Abu Bakr al-Baghdadi, the leader of the Islamic State. The extremist group encourages its followers who seek to commit violence in its name to make public pledges of support.
The Justice Department said in a statement it initially withheld the names so as not to give extremists "a publicity platform for hateful propaganda," but the omissions became an unnecessary distraction.
Shortly after the call with a 911 operator, Mateen had three conversations with crisis negotiators in which he identified himself as an Islamic soldier and told a negotiator to tell America to stop bombing Syria and Iraq. He said that was why he was "out here right now," according to the excerpt.
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City officials have refused to provide hundreds of 911 calls to The Associated Press and a coalition of news organizations, citing confidentiality under Florida law, and arguing that an ongoing investigation kept the tapes secret. Hopper also said Monday that the tapes would not be released out of respect for the victims.
"Yes, the audio was compelling, but to expose that now would be excruciatingly painful to exploit them in this way," Hopper said.
Hopper also said: "Part of redacting is to not give credence to individuals who have done terrorist acts in the past. They are not going to propagate their violent rhetoric."
The AP and others requested the 911 tapes and related data, a common practice after such major events. The recordings could offer insight into how law enforcement responded.
Also at Monday's news conference, Orlando police Chief John Mina said that if any fire from responding officers hit victims at the club, gunman Mateen bears the responsibility. He wouldn't give further details but said: "Here's what I will tell you. Those killings are on the suspect, on the suspect alone in my mind." He stressed that the officers "acted heroically."
Mina acknowledged that questions have been raised by media outlets and the public about whether Orlando police waited too long after the start of the rampage at 2 a.m. to send in a SWAT team about 5 a.m.
He said an exchange of fire between police and Mateen shortly after 2 a.m. prompted the attacker to retreat into a bathroom and take hostages, shifting the incident from a shooting to a hostage-taking. Mina said there was no additional gunfire for about three hours until the SWAT team entered the building, although survivors have describing at least some firing taking place inside one of the bathrooms.
Surviving hostage Patience Carter, in a live televised interview two days after the attacks, described the attacker firing when he entered the bathroom and more firing when the SWAT team burst into the building.
"I think there's this misconception that we didn't do anything for three hours," Mina said. "I'm trying to clarify: That's absolutely not true. Our officers were within the club within minutes, exchanging gunfire with the suspect, forced him to stop shooting and retreat into the bathroom."
"From there, we let our negotiator take over and try to negotiate this to a peaceful resolution in an effort to save lives while our SWAT team set up," Mina said.
Meanwhile, hospital officials said four people remained in critical condition Monday morning, more than a week after they were wounded in the attack.
Orlando Regional Medical Center said 18 victims from the shooting were still at the hospital and three more surgeries were scheduled for Monday. The other 14 patients are listed in stable condition.
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Armed with a semi-automatic weapon, Mateen went on a bloody rampage at the Pulse nightclub June 12. He died in a hail of gunfire after police stormed the venue.
U.S. Attorney General Loretta Lynch will travel to Orlando on Tuesday to meet with investigators. She said that a key goal of the investigation was to determine why Mateen targeted the gay community. The victims were predominantly gay and Hispanic since it was "Latin night" at Pulse.
Around Orlando, people left balloons, flowers, pictures and posters at a makeshift memorial in front of the city's new performing arts center and at Orlando Regional Medical Center where 49 white crosses were emblazoned with red hearts and the names of the victims.
The crosses were built by a Chicago carpenter with a history of constructing crosses for victims of mass shootings. Greg Zanis drove from Illinois to Orlando last week and installed the crosses at the medical center, where many of the 53 shooting victims who survived were taken for treatment.
Dr. Khurshid Ahmed was part of a group of Muslim-Americans at a Sunday vigil attended by tens of thousands who held signs reading, "Muslims Condemn Extremism." A letter from the chairman of the Senate Homeland Security Committee, Republican Ron Johnson of Wisconsin, said Mateen wrote on Facebook that "real Muslims will never accept the filthy ways of the West."