ORLANDO (Florida) • In the worst mass shooting in United States history, 50 people died and 53 others were injured when a heavily armed gunman opened fire and seized hostages at a gay nightclub in Orlando.
The police, who killed the shooter, classified yesterday's attack as a "terror incident".
Terrified survivors described how the gunman - identified as Omar Mateen, a 29-year-old US citizen - raked the club with bullets.
One clubgoer said he heard at least 40 shots fired. Another said there was "blood everywhere".
A police Swat team was called in to storm the venue.
"We have cleared the building, and it is with great sadness that I share we have not 20, but 50 casualties, in addition to the shooter," Mayor Buddy Dyer told a news briefing in Orlando. "There are another 53 that are hospitalised."
The death toll far exceeded the 32 people killed at Virginia Tech in 2007, and the 26 gunned down at an elementary school in Newtown, Connecticut, in 2012.
The shooting was also the second such incident in Orlando in just over 24 hours, coming after singer Christina Grimmie was shot dead by a gunman late on Friday.
Federal Bureau of Investigation official Ronald Hopper told reporters that officials were "confident" there was no immediate further threat to the area, or to the US.
But because of the scale of the crime, Mr Dyer declared a city- wide state of emergency and also asked the Florida governor to take the same measure state-wide.
President Barack Obama was briefed on the shooting and was expected to deliver a statement.
Mr Hopper said the US authorities were looking into whether Omar had "leanings" towards Islamic extremism. A Twitter account linked to the Islamic State in Iraq and Syria militant group posted a photo purported to be of Omar.
The chaotic events unfolded over a three-hour period, starting at about 2am on Sunday US time, when shots rang out at the Pulse nightclub near closing time. An off-duty police officer working security at the club exchanged fire with the gunman, said Orlando police chief John Mina.
"The suspect at some point went back inside the club where more shots were fired. This did turn into a hostage situation," he told reporters. That was when the decision was taken to rescue the hostages.
The police stormed the venue, using explosives and breaking through a wall with a wheeled armoured vehicle. Mr Mina said about 30 people were rescued in the operation. The injured were rushed to hospitals.
At Orlando Regional Medical Centre, where some of the gunshot victims were being treated, the scene was sombre as many had not been able to locate their loved ones.
Mr C. J. Walker, 30, drove 130km to Orlando from Tampa seeking information about his sister, one of the nightclub's DJs. She normally worked on Saturday nights, and he had not been able to reach her by phone or on social media. He finally learnt that she had not worked on Saturday night and was safe.
"Unfortunately, it's not going to be like this for so many other people," he said.
AGENCE FRANCE-PRESSE, REUTERS, NEW YORK TIMES
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