At least 19 people were killed and 50 injured Monday night in an explosion at an Ariana Grande concert in Manchester, England, that police are treating as a possible terrorist attack.
The explosion happened near an entrance to the 21,000-seat arena just minutes after Grande's concert ended and the singer left the stage, witnesses said.
Manchester Arena reported on its Facebook page that the incident took place outside the venue in a public space.
Law enforcement cordons blocked off the entire area as a swarm of police cars and ambulances moved in and began evacuating bleeding concert patrons.
"This is currently being treated as a terrorist incident until police know otherwise," Manchester police said in a statement.
Grande was not injured. "Ariana is okay. We are further investigating what happened," said Joseph Carozza, the artist's publicist with Republic Records, a division of Universal Music group.
One witness, who had left the arena just after the end of the concert, heard a "huge explosion" near one of the arena's exits, close to where concertgoers picked up their tickets before the show.
"Everyone stopped and all talking stopped," Charlotte, 18, from Manchester, wrote in a direct message on Twitter. Then she saw people running out of the exits. "Everyone was running and screaming. And people was screaming evacuate."
Lauren Sanders, 15, was near the stage when she heard an explosion that seemed to come from near the entrance of the theater, where the audience had streamed toward the exits, perhaps two minutes after Grande left the stage.
"Then everyone who was leaving started screaming and running the other way to another exit," Sanders wrote in a direct message on Twitter. A huge Grande fan, she had come to the concert with her mother. "I grabbed my mum's hand and started running, following a lot of others towards an exit." Outside, police were everywhere, trying to clear the area, she said.
Matt Ledger, 19, was with two of his friends at the concert when he heard one of the explosions. "Everyone starting sprinting and grabbing each other," Ledger said in a phone interview. "When I got outside I saw a few people laying on the grass and their heads were bleeding."
Ledger, who lives two hours outside of Manchester and came in for the concert, said he ran 10 minutes away to a bar, where he took shelter for two hours.
Some survivors fled to the nearby Steven Charles Snooker Club, where a bartender reported hearing a sound from the arena like "thunder."
"We've got four girls here _ trying to get them sorted to get picked up. There was a gentleman on the floor with his leg all bleeding and a woman with blood down one side of her face," the bartender, who gave his name as Tyler, told the Press Association. "One girl had a panic attack and another had streaming tears, a woman had a heart attack just outside."
As in previous incidents in Europe, people took to social media to offer lifts, rooms for the night and tea to those in need using the hashtag #RoomForManchester. Others used the hashtag to send out anguished pleas for information about the missing. "My friend is missing in the concert haven't heard of him please contact me #Manchester #RoomForManchester worried and sick now," read one tweet.
Grande was scheduled for additional performances on her Dangerous Woman Tour on Thursday and Friday at London's O2 Arena, according to the website of the tour prompter, Live Nation UK.
