‘ISIS man’ kills 50 in worst mass slaughter in US

• US security officials say Afghan-origin American Omar Mateen opened indiscriminate fire at gay nightclub in Orlando
• American media reports say Mateen had pledged allegiance to feared ultra-violent extremist outfit ISIS
• ‎Mateen’s father apologises for son’s act, claims killer was not religiously motivated

After calling 911 to declare his allegiance to a terrorist group, a gunman here killed 50 people and wounded 53 in a crowded gay nightclub early Sunday, the worst mass shooting slaughter in American history, law enforcement officials said.

The gunman was Omar Mateen, 29, an American citizen living in Fort Pierce, Fla., federal law enforcement officials said.

Local law enforcement officials and Department of Homeland Security officials have told members of Congress that the gunman made the 911 call shortly before the attacks and swore allegiance to the Islamic State terrorist group.

But officials cautioned that even if Mr. Mateen was inspired by the group, there was no indication so far that he was trained or instructed by them, or had any direct connection with them. The pair who killed 14 people in San Bernardino, Calif., in December also proclaimed allegiance to the Islamic State, but investigators do not believe they had any contact with the group.

Mr. Mateen, who court records show was born in New York and had been married and divorced, had drawn the attention of the F.B.I. in the past, law enforcement officials said, but they could not provide details. Yet he was able to work as a security guard.

“The F.B.I. is approporiately investigating this as an act of terror,” President Obama said Sunday from the White House. He said that the gunman was clearly ”filled with hatred” and that the investigators were seeking to determine any ties to overseas terrorist groups.

“In the face of hate and violence, we will love one another,” he said. “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 has so many times before following mass shootings, the president said the shooting demonstrated again 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,” the president 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.”

The killer stormed the Pulse nightclub armed with an AR-15-style assault rifle and a handgun at about 2 a.m., while more than 300 people were inside dancing and drinking, John Mina, the Orlando police chief, said. He shot about one-third of the people in the packed club, mowing down patrons while hundreds of people, some of them bleeding, fled down the darkened streets of the surrounding neighborhood.

The result was the worst terrorist attack on American soil since Sept. 11, 2001, and the deadliest attack in the nation’s history on a specifically gay gathering.

The gunman holed up inside with dozens of people effectively held hostage, some of them hiding in a restroom frantically calling for help, until about 5 a.m., when a police SWAT team, using an armored vehicle and stun grenades, raided the building and killed him.

In that assault, an officer was wounded, his life saved by a Kevlar helmet that deflected a bullet, and at least 30 people were rescued, Chief Mina said. Some survivors escaped under cover of what the police called two “discretionary explosions.”

Ronald Hopper, an assistant agent in charge of the F.B.I.’s Tampa Division, raised the possibility that the killer was an Islamist radical, and law enforcement officials said they were investigating the massacre as a terrorist attack. The F.B.I. set up a hotline for tips.

“We do have suggestions that that individual may have leanings towards that, that particular ideology,” Agent Hopper said. “But right now we can’t say definitively, so we’re still running everything around.”

Some past terrorist attacks, like the San Bernardino killings, were carried out in the name of Islam by people, many of them born and raised in the West, who were “self-radicalized.” Terrorist groups have not claimed responsibility for the Orlando shooting as yet, but a social messaging account linked to the Islamic State gloated about the attack.

The Islamic State in particular has encouraged “lone wolf” attacks in the West, a point reinforced recently by a spokesman for the group, Abu Muhammad al-Adnani, in his annual speech just before the holy month ofRamadan. In past years, the Islamic State and Al Qaeda ramped up attacks during Ramadan.

“Make it, Allah permitting, a month of hurt on the infidels everywhere,” Mr. Adnani said, according to a translation provided by the SITE Intelligence Group. Noting that some supporters have lamented that they cannot strike at military targets, he took pains to explain why killing civilians in the land of the infidel is not just permitted but encouraged.

Rasha Mubarak, the Orlando regional coordinator of the Council on American-Islamic Relations, released a statement saying: “We condemn this monstrous attack and offer our heartfelt condolences to the families and loved ones of all those killed or injured. The Muslim community joins our fellow Americans in repudiating anyone or any group that would claim to justify or excuse such an appalling act of violence.”

The toll of the dead and injured far exceeded those of 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 were killed.

Pulse, which calls itself “Orlando’s Latin Hotspot,” was holding its weekly “Upscale Latin Saturdays” party with three D.J.s and a midnight show. Witnesses described a scene of chaos and confusion, and some said it was hard at first to realize that the gunshots were not part of the loud, pulsing dance music.

“We were dancing by the hip-hop area when I heard shots, bam, bam, bam, and the only thing I could think of was to duck, but I ran out instead,” said Joel Figueroa, 19, of Orlando, who had been inside. “Everybody was screaming and running toward the front door. I didn’t get to see the shooter.”

He said a friend of his had been shot three times and taken to a hospital.

Ray Rivera, a D.J.at the club, was playing reggae music in the patio area when the shooting started, while Latin music played inside the building.

“I heard shots, so I lower the volume of the music to hear better because I wasn’t sure of what I just heard,” Mr. Rivera said. “I thought it was firecrackers, then I realized that someone is shooting at people in the club.

“I heard like 40 shots coming from the main area of the club,” he continued. “I ran away through a side gate. I saw bodies on the floor, people on the floor everywhere. It was a chaos, everybody trying to get out.”

Mr. Rivera, 42, who has worked at Pulse for years, said: “This is a nice club, decent, people come from all over to dance and have a good time. Young people. A lot of young people were there last night. This is crazy.”

The club posted a message on its Facebook page about 3 a.m.: “Everyone get out of pulse and keep running.”

People streamed out of the club into a chaotic situation with little idea of where to go. “Cops were saying, ‘Go, go, clear the area,’” Christopher Hansen told an Orlando TV station. “You don’t know who’s what and who’s where.”

Witnesses and police officers carried bleeding people down the streets, sometimes loading them into police vehicles for the drive to hospitals rather than waiting for ambulances. The club is just three blocks down South Orange Avenue from Orlando Regional Medical Center, the region’s primary trauma center, and two other hospitals also took in victims.

On its Twitter feed, the Orlando Police Department asked other residents to “stay away from area” and said it was seeking support from state and federal agencies. But hundreds of terrified people gathered at the cordon that the police set up around the area, while others flocked to hospitals, waiting for word on relatives and friends who had been in the club.

“A girlfriend of my son called and said, ‘He got shot, he got shot,’ and she was crying,” one woman told CNN outside the medical center. She said she could not find her son, or even get information on where he had been taken.

Phone camera videos showed police cars, ambulances and other emergency vehicles outside the club on South Orange Avenue in downtown Orlando. Streets around the club were shut down for several blocks.

Dozens of officers, paramedics and firefighters from the Orlando police, the Orange County Sheriff’s Office, the F.B.I. and three fire departments were called to the scene.

“Just to look into the eyes of our officers told the whole story,” Chief Mina said after his officers had taken control of the building and found all the bodies. “You could tell that they were all shaken by this incident, by what they saw.”

In the hours after the shooting, local television stations broadcast camera phone videos that captured the chaos at and near Pulse. One of the videos clearly captured the rescue attempt. Shots could be heard as men and women ran from the nightclub.

Orlando Regional Medical Center was placed on lockdown after receiving the first of the victims. “Only essential workers are being allowed access into the building,” the hospital said in a statement.

“Out of an abundance of caution, Arnold Palmer Hospital and Winnie Palmer Hospital have also been placed on lockdown,” the statement added.

“Please keep everyone in your prayers as we work through this tragic event,”the nightclub’s post said. “Thank you for your thoughts and love.”

The Gay Lesbian, Bisexual, Transgender Community Center of Central Florida said it was offering grief counseling to victims and survivors.

Officials at Orlando Regional Medical Center asked members of the families of victims and missing people to gather at the north entrance, where they would be escorted inside.

The slaughter at Pulse occurred a day after the singer Christina Grimmie, a star of YouTube and the reality TV show “The Voice,” was shot down after a concert in Orlando. The police said she had been killed by a St. Petersburg, Fla., man who drove to Orlando with the specific intention to kill Ms. Grimmie. The man, Kevin James Loibl, killed himself moments later.

Chief Mina said Mr. Loibl had traveled to Orlando with two handguns, several loaded magazines and a hunting knife. Police officials were examining his telephone and computer to try to determine a motive.