The first came when an off-duty officer who had been working at the nightclub responded to shots fired at about 2 a.m., Chief Mina said. Additional officers rushed to the scene, he said, and entered the nightclub where they engaged in a gun battle with Mr. Mateen, forcing him to retreat to a bathroom where officers believed he had four to five hostages. About 15 to 20 people were in another bathroom.
“At that time we were able to save and rescue dozens and dozens of people and get them out of the club,” Chief Mina said. A SWAT team was called and took up positions in a bathroom across from where Mr. Mateen had holed up.
Negotiators also began to talk with Mr. Mateen, whom Chief Mina described as “cool and calm.”
Mr. Mateen made statements that led police officers to think he was going to begin killing more people, the chief said, and he called 911.
“He really wasn’t asking for a whole lot, we were doing most of the asking,” Chief Mina said.
Chief Mina said Mr. Mateen’s talk of explosives spurred the police’s decision to start the rescue operation and try to breach the bathroom.
But an explosive placed on the wall did not penetrate completely, so officers used an armored vehicle to punch a hole about two feet off the ground, allowing hostages to flee. Mr. Mateen also came through the breach in the wall, Chief Mina said, and was killed in a shootout with the police.
Mass Shooting at Orlando Nightclub
Jim Young/Reuters
When asked during the news conference if there was a chance that people might have been struck by friendly fire, or in the crossfire, Chief Mina said: “I will say that is all part of the investigation. But I will say when our SWAT officers, about eight or nine officers, opened fire, their backdrop was a concrete wall. And they were being fired upon, so that is all part of the investigation.”
At hospitals and gathering spots nearby, relatives and friends of the clubgoers who remained unaccounted for began to lose hope that their loved ones had somehow survived the mass shooting. And those who had already learned that their loved ones had died began to plan for funerals.
“I cannot imagine being one of the parents or knowing your loved one may be among the deceased and waiting to find out,” Mr. Dyer said. The authorities adjusted the death toll on Monday, saying that the 50 people killed included the gunman. Orlando Health, which has a network of medical facilities in the area, said 43 victims remained in the hospital, including six who would undergo operations on Monday.
Mr. Mateen’s father, Seddique Mir Mateen, posted a video on his Facebook page early on Monday in which he expressed regret and confusion about why his son had carried out the mass killing.
“I don’t know what caused this,” said Mr. Mateen, speaking in Dari, a language spoken in Afghanistan. “I did not know and did not understand that he has anger in his heart.”
GRAPHIC
What Happened Inside the Orlando Nightclub
Accounts of what happened from officials and witnesses.
“My son, Omar Mateen, was a very good boy, an educated boy, who had a child and a wife, very respectful of his parents,” he said.
At Monday’s news conference, A. Lee Bentley, the United States attorney for Central Florida, said the investigators had collected a large amount of electronic and criminal evidence and were trying to determine whether Mr. Mateen acted alone.
“If anyone else was involved in this crime,” Mr. Bentley said, “they will be prosecuted.”
The attacker, a 29-year-old who was born in New York, turned what had been a celebratory night of dancing to salsa and merengue music at the crowded Pulse nightclub into a panicked scene of unimaginable slaughter, the floors slicked with blood, the dead and the wounded piled atop one another. Terrified people poured onto the darkened streets of the surrounding neighborhood, some carried wounded victims to safety and police vehicles were pressed into service as makeshift ambulances to rush people to hospitals.
Orlando
FLORIDA
408
Orlando Regional Medical Center
441
Site of shooting
Pulse nightclub
Conway
527
4
Edgewood
Oak Ridge
2 Miles
Joel Figueroa and his friends “were dancing by the hip-hop area when I heard shots, bam, bam, bam,” he said, adding, “Everybody was screaming and running toward the front door.”
It was the worst act of terrorism on American soil since Sept. 11, 2001, and the deadliest attack on a gay target in the nation’s history, though officials said it was not clear whether some victims had been accidentally shot by law enforcement officers.
Gov. Rick Scott of Florida said on Monday that he had asked President Obama to issue a federal emergency declaration for his state.
“Yesterday’s terror attack was an attack on our state and entire nation,” Mr. Scott said in a statement. “This morning, I have asked President Obama to declare an emergency so that the full resources of the federal government can be made available for all those impacted by this horrific massacre.”
In a letter to Mr. Obama, Mr. Scott sought two forms of federal aid: “provision of health and safety measures,” as well as “management, control and reduction of immediate threats to public health and safety.” An emergency declaration by Mr. Obama would give Florida up to $5 million in initial federal funding.
The toll is larger than the number of murders in Orlando over the previous three years. Of an estimated 320 people in the club, nearly one-third were shot. The casualties far exceeded those in the 2007 shooting at Virginia Tech, where 32 people were killed, and the 2012 shooting at an elementary school in Newtown, Conn., where 26 people died.
“In the face of hate and violence, we will love one another,” Mr. Obama said in a special address from the White House. “We will not give in to fear or turn against each other. Instead, we will stand united as Americans to protect our people and defend our nation, and to take action against those who threaten us.”
As he had done after several previous mass shootings, the president said the shooting demonstrated the need for what he called “common sense” gun measures.
“This massacre is therefore a further reminder of how easy it is for someone to get their hands on a weapon that lets them shoot people in a school or a house of worship or a movie theater or a nightclub,” Mr. Obama said. “We have to decide if that’s the kind of country we want to be. To actively do nothing is a decision as well.”
Mass Shootings in the U.S.
This partial list dates to 2007, the year of what used to be the deadliest mass shooting in U.S. history.
The shooting quickly made its way into the presidential campaign. Donald J. Trump, the presumptive Republican nominee, who has accused Mr. Obama of weakness on radical Islam and has called for barring Muslim immigrants, suggested on Twitter that the president should resign.
“Appreciate the congrats for being right on radical Islamic terrorism,” he wrote. “I don’t want congrats, I want toughness & vigilance. We must be smart!”
Hillary Clinton, the presumptive Democratic nominee, released a statement saying: “We need to redouble our efforts to defend our country from threats at home and abroad. That means defeating international terror groups, working with allies and partners to go after them wherever they are, countering their attempts to recruit people here and everywhere, and hardening our defenses at home.”
Fears of violence led to heightened security at lesbian, gay, bisexual and transgender events and gathering places around the country. Law enforcement officials in Santa Monica, Calif., confirmed the arrest on Sunday of a heavily armed man who said he was in the area for West Hollywood’s gay pride parade. The authorities, however, said they did not know of any connection between the California arrest and the Orlando shooting.
The F.B.I. investigated Mr. Mateen in 2013 when he made comments to co-workers suggesting he had terrorist ties, and again the next year, for possible connections to Moner Mohammad Abusalha, an American who became a suicide bomber in Syria, said Ronald Hopper, an assistant agent in charge of the bureau’s Tampa Division. But each time, the F.B.I. found no solid evidence that Mr. Mateen had any real connection to terrorism or had broken any laws.
Mr. Mateen, who lived in Fort Pierce, Fla., was able to continue working as a security guard with the security firm G4S, where he had worked since 2007, and he was able to buy guns. The federal Bureau of Alcohol, Tobacco, Firearms and Explosives said Mr. Mateen had legally bought a long gun and a pistol in the past week or two, though it was not clear whether those were the weapons used in the assault, which officials described as a handgun and an AR-15 type of assault rifle.
A former co-worker, Daniel Gilroy, said Mr. Mateen had talked often about killing people and had voiced hatred of gays, blacks, women and Jews.
Hours later, the Islamic State, also known as ISIS or ISIL, claimed responsibility in a statement released over an encrypted phone app used by the group. It stated that the attack “was carried out by an Islamic State fighter,” according to a transcript provided by the SITE Intelligence Group, which tracks jihadist propaganda.
But officials cautioned that even if Mr. Mateen, who court records show was briefly married and then divorced, was inspired by the group, there was no indication that it had trained or instructed him, or had any direct connection with him. Some other terrorist attackers have been “self-radicalized,” including the pair who killed 14 people in December in San Bernardino, Calif., who also proclaimed allegiance to the Islamic State, but apparently had no contact with the group.
