UPDATE 5/22/17, 8:24 p.m. ET:
The Manchester Arena has tweeted that “the incident took place outside the arena in a public space,” not inside, as had previously been reported:
UPDATE 5/22/17, 8:19 p.m. ET:
Local police have confirmed 19 dead, 50 injured:
Reports from the BBC, NBC News, and other organizations suggest that many of the injuries are crush injuries from the stampede to exit after the explosion.
The Los Angeles Times, meanwhile, reports that Ariana Grande herself is OK:
UPDATE 5/22/17, 8:05 p.m. ET:
NBC News is reporting that UK authorities are telling American officials that, based on “forensic indications,” the explosion appears to be the result of a suicide bomber with some kind of backpack bomb. The bomb apparently went off near the box office in the foyer/concourse as the concert was about to end.
Also, multiple senior law enforcement officials tell NBC that at least 20 people are dead with hundreds injured:
UPDATE 5/22/17, 8:00 p.m. ET:
Ceylan Yeginsu, a London-based reporter for The New York Times, tweeted that the BBC has an eyewitness who was thrown through arena doors by the force of an explosion:
UPDATE 5/22/17, 7:58 p.m. ET:
Sky News, The Manchester Evening News, and various other news organizations have been running or linking to this dash cam video, said to be about a quarter mile away from the arena, which picks up the sound of an explosion:
UPDATE 5/22/17, 7:46 p.m. ET:
The regional ambulance service that covers Manchester has tweeted that “a large number of resources” are tied up with the injuries at Manchester Arena:
The Guardian's Helen Pidd is reporting that people are still exiting the area, some badly injured:
On CNN, one witness, who was being interviewed by phone while in tears, said she saw approximately 20-30 dead bodies as she was attempting to get out, with “blood everywhere.”
UPDATE (5/22/17, 7:26 p.m. ET:
One witness, interviewed by phone on Sky News, spoke of smelling smoke and something burning while fleeing the arena. In addition, Sky, NBC News, and some other outlets are using the word “explosion” without any qualification.
The Greater Manchester Police Department in the U.K. is reporting an “incident” — allegedly an explosion — at the Manchester Arena Monday evening (Eastern Time) during an Ariana Grande concert.
The have released a statement on Twitter “confirming fatalities” and injuries.
Grande was wrapping up a concert at the time of the supposed explosion, as reported by Sky News.
Witness Majid Khan said:
"I and my sister, along with a lot of others were seeing Ariana Grande perform at Manchester Arena, and we were all exiting the venue when around 10.40-10,45pm-ish a huge bomb-like bang went off that hugely panicked everyone and we were all trying to flee the arena.
It was one bang and essentially everyone from the other side of the arena where the bang was heard from suddenly came running towards us.
Everyone was in a huge state of panic, calling each other as some had gone to the toilet whilst this had gone off, so it was just extremely disturbing for everyone there."
Hannah Dane, an attendee at the concert, told The Guardian that there was “quite a loud explosion heard from inside the Manchester arena and it shook, then everyone screamed and tried to get out.”
The Independent reports that Twitter posts claim “that concertgoers were fleeing covered in blood and crying.”
The incident occurred toward the end of the concert. Witnesses have claimed that the noise sounded like a “gunshot” or possible a speaker exploding.
Some Twitter posts show medical response personnel on the scene, allegedly treating injured persons:
It is unknown at this time if Grande was harmed in the incident.
This is a breaking story and will be updated as information becomes available.