Police work at Manchester Arena after reports of an explosion at the venue during an Ariana Grande gig in Manchester, England Monday, May 22, 2017. (AP Photo)
Manchester: An explosion struck an Ariana Grande concert attended by thousands of young music fans in northern England, killing at least 22 people and injuring dozens in what police said on Tuesday they suspected was a terrorist attack.
Greater Manchester Police Chief Constable Ian Hopkins says police are treating the blast as an act of terrorism "until we know otherwise." The local ambulance service says 59 people were taken to hospitals.
There was panic after the explosion, which struck around 10:30 p.m. (2130 GMT) Monday night as Grande was ending the concert, part of her Dangerous Woman Tour.
The singer, who was not injured, tweeted hours later: "Broken. From the bottom of my heart, I am so so sorry. I don't have words."
Police cars, bomb-disposal units and 60 ambulances raced to the scene as the scale of the carnage became clear. More than 400 officers were deployed overnight after the blast occurred.
Manchester Arena said on its website that the blast struck outside the venue as concertgoers were leaving. Some eyewitnesses said it happened in the foyer of the arena just after the concert ended.
One witness said Grande had just finished her final song and said "Thank you, Manchester," before leaving the stage.