ORLANDO, Fla., June 13 (Reuters) - A man armed with an assault rifle and pledging loyalty to Islamic State militants killed 50 people during a gay pride celebration at a nightclub in Orlando, Florida, early on Sunday in the deadliest mass shooting in U.S. history, a rampage President Barack Obama denounced as an act of terror and hate.
Police killed the gunman, who was identified as Omar Mateen, 29, a New York-born Florida resident and U.S. citizen who was the son of immigrants from Afghanistan and had twice been questioned by FBI agents in recent years, authorities said.
Mateen's former wife described him as emotionally and mentally disturbed with a violent temper, yet who aspired to be a police officer. He also worked as an armed guard for the security firm G4S, the world's largest, according to the company.
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Police cars and fire trucks are seen outside the Pulse night club where police said a suspected gunman left multiple people dead and injured in Orlando, Florida, June 12, 2016. Orlando Police Department/Handout via REUTERS[/caption]
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People gather as police conduct questioning near Pulse nightclub, where people were killed by a gunman in a shooting rampage in Orlando, Florida June 12, 2016. REUTERS/Kevin Kolczynski[/caption]
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Police lock down Orange Avenue around Pulse nightclub, where people were killed by a gunman in a shooting rampage in Orlando, Florida June 12, 2016. REUTERS/Kevin Kolczynski[/caption]
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Friends and family members embrace outside the Orlando Police Headquarters during the investigation of a shooting at the Pulse nightclub, where people were killed by a gunman, in Orlando, Florida, U.S June 12, 2016. REUTERS/Steve Nesius[/caption]
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Officers arrive at the Orlando Police Headquarters during the investigation of a shooting at the Pulse nightclub, where people were killed by a gunman, in Orlando, Florida, U.S June 12, 2016. REUTERS/Steve Nesius[/caption]
Law enforcement officials were probing evidence suggesting the attack was inspired by Islamic State militants, although they said there was no proof that Mateen had worked directly with the group.
As the shooting rampage was unfolding, Mateen "made calls to 911 this morning in which he stated his allegiance to the leader of the Islamic State," said Ronald Hopper, the FBI's assistant special agent in charge on the case.
Shots rang out at the crowded Pulse nightclub in the heart of Orlando, one of the most popular U.S. tourist destinations, as some 350 patrons were attending a Latin music event in conjunction with gay pride week celebrations. Clubgoers described scenes of terror and pandemonium, with one man who escaped saying he hid under a car and bandaged a wounded stranger with his shirt.
Orlando Police Chief John Mina and other city officials answer the media's questions about the Pulse nightclub shooting in Orlando, Florida June 12, 2016. REUTERS/Kevin Kolczynski[/caption]
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Friends and family members embrace outside the Orlando Police Headquarters during the investigation of a shooting at the Pulse nightclub, where people were killed by a gunman, in Orlando, Florida, U.S June 12, 2016. REUTERS/Steve Nesius[/caption]
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Friends and family members embrace outside the Orlando Police Headquarters during the investigation of a shooting at the Pulse night club, where as many as 20 people have been injured after a gunman opened fire, in Orlando, Florida, U.S June 12, 2016. REUTERS/Steve Nesius[/caption]
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People gather for a candlelight vigil in remembrance for mass shooting victims in Orlando, from San Diego, California, U.S. June 12, 2016. REUTERS/Mike Blake[/caption]
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A rainbow flag is held up with the name of the gay nightclub where the worst mass shooting in U.S. history occured in Orlando,Florida, during a vigil in front of the White House in Washington, U.S., June 12, 2016. REUTERS/Joshua Roberts[/caption]
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Police forensic investigators work at the crime scene of a mass shooting at the Pulse gay night club in Orlando, Florida, U.S. June 12, 2016. REUTERS/Jim Young[/caption]
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Imam Syed Shafeeq Rahman of the Islamic Center of Fort Pierce speaks with the media following a prayer for victims of the Orlando shooting, in Fort Pierce, Florida June 12, 2016. REUTERS/Joe Skipper[/caption]
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Orlando residents light candles during a vigil at Lake Eola Park for victims of an early morning shooting attack at a gay nightclub in Orlando, Florida, U.S June 12, 2016. REUTERS/Steve Nesius[/caption]
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Police forensics investigators work at the crime scene of a mass shooting at the Pulse gay night club in Orlando, Florida, U.S. June 12, 2016. REUTERS/Carlo Allegri[/caption]
The attack came six months after a married couple in California - a U.S.-born son of Pakistani immigrants and a Pakistani-born woman he married in Saudi Arabia, fatally shot 14 people in San Bernardino in an attack inspired by Islamic State.
That couple died in a shootout with police hours after their attack on a holiday party attended by the husband's co-workers.
'UNIMAGINABLE'
The Florida shooting evolved into a hostage situation, which a team of SWAT officers ended around dawn when they used armored cars to storm the club before killing the gunman. It was unclear when the victims were killed.
Officials in Orlando, a city of 270,000 people and home to tourist attractions including the Disney World resort, were visibly shocked at the high death toll, which they had initially put at 20.
"We're dealing with something that we never imagined and is unimaginable," Orlando Mayor Buddy Dyer said. He said 39 people died inside the club, two outside, and nine others died after being rushed to hospital.
Orlando Regional Medical Center hospital said it had admitted 44 victims, including nine who died, and had carried out 26 operations on victims.
The city began releasing names of the victims on Sunday, with the first seven identified as Edward Sotomayor Jr., Stanley Almodovar, Luis Omar Ocasio-Capo, Juan Ramon Guerrero, Eric Ivan Ortiz-Rivera, Peter Gonzalez-Cruz and Luis Vielma.
Mateen had twice been interviewed by FBI agents, in 2013 and 2014, after making comments to co-workers indicating he supported militant groups, but neither interview led to evidence of criminal activity, the FBI's Hopper said.
Hopper said Mateen was questioned in 2014 about his contacts with Moner Mohammad Abu-Salha, a U.S. citizen who also had lived in Florida and became a suicide bomber in Syria that year.
Near Boulder, Colorado, Mateen's former wife, Sitora Yusufiy, told reporters he worked for a time as a correctional officer at a detention center for juvenile delinquents in Fort Pierce, Florida, and had once sought admission to a police academy.
She said she had been beaten and otherwise physically abused by Mateen during outbursts of temper in which he would "express hatred towards everything." Eventually, she was "rescued" from Mateen by family members who intervened in a stormy marriage that ultimately ended in divorce, she said.
"I know he had a history of steroids," Yusufiy told reporters outside a home where she was staying with a man she identified as her current fiance. She also described Mateen as "emotionally unstable," "mentally ill" and bipolar.
Deborah Sherman, an FBI spokeswoman in Denver, confirmed that federal agents had interviewed Yusufiy in Colorado.
The imam of the Florida mosque where Mateen attended prayers for nearly 10 years described him as a soft-spoken man who would visit regularly but rarely interact with others in the congregation.
CANDIDATES WEIGH IN
Within hours of the shooting, the presumptive presidential nominees of both major political parties weighed in with statements on the tragedy.
Trump, who has called for a temporary ban on Muslims entering the United States, said he was "right on radical Islamic terrorism" and called on Obama to resign because he did not say the words "radical Islam" in his statement responding to the shooting.
Clinton echoed Obama's comments calling the attack both an act of terror and a hate crime, adding that the massacre "reminds us once more that weapons of war have no place on our streets."
If confirmed as an act of terrorism, it would be the deadliest such attack on U.S. soil since Sept. 11, 2001, when al Qaeda-trained hijackers crashed jetliners into New York's World Trade Center, the Pentagon and a field in Pennsylvania, killing some 3,000 people.
The choice of target was especially heart-wrenching for members of the U.S. lesbian, gay, bisexual and transgender community, said LGBT advocacy group Equality Florida.
"Gay clubs hold a significant place in LGBTQ history. They were often the only safe gathering place and this horrific act strikes directly at our sense of safety," the group said in a statement. "We will await the details in tears of sadness and anger."
In an apparently unrelated incident on Sunday, a heavily armed man from Indiana who said he was headed to a Los Angeles-area gay pride festival was arrested in nearby Santa Monica, California, where police found guns and chemicals to make explosives in his car.
