British police say at least 22 people were killed and 59 wounded in an explosion Monday night outside a concert venue in Manchester, England.
“We have been treating this as a terrorist incident and we believe at this stage the attack last night was conducted by one man,” Ian Hopkins, chief constable of Greater Manchester Police, said Tuesday.
Hopkins said investigators believe the attacker was carrying an improvised explosive device, which he detonated, and that he died at the site.
Police are working with national counterterrorism and intelligence officials to figure out more details about the attacker with a priority on determining whether he was acting alone or as part of a network, Hopkins said.
The blast happened in the lobby of the 21,000 seat Manchester Arena at the end of a concert by American pop star Ariana Grande.
“Broken. From the bottom of my heart, I am so, so sorry,” Grande wrote on Twitter after the blast. “I don’t have words.”
“This was a barbaric attack, deliberately targeting some of the most vulnerable in our society, young people, children, out at a pop concert,” said British Home Secretary Amber Rudd.
British Prime Minister Theresa May said her thoughts are with the victims of what she called an “appalling terrorist attack.” May and Jeremy Corbyn, the leader of the opposition Labour Party, agreed to suspend campaigning ahead of the country’s June 8 elections.
After the attack, Manchester police deployed hundreds of officers overnight and at one point conducted a precautionary controlled explosion near the arena of an object they later said turned out to not be anything suspicious.
Video from the concert showed thousands of concertgoers, many of them young girls, scrambling and screaming, trying to escape the building.
Some witnesses said the ground near the blast was covered with nuts and bolts.
Abandoned shoes, phones and jackets were scattered throughout the arena.
“It was a huge explosion. You could feel it in your chest. It was chaotic. Everybody was running and screaming just trying to get out,” a concertgoer told Reuters.
Worried parents who had brought their children to the show crowded the streets outside the building. A nearby hotel opened its doors to the kids looking for their mothers and fathers.
Cab drivers turned off their meters and offered to drive people from the ill-fated concert to wherever they want to go.
The U.S. Department of Homeland Security said it was monitoring the situation in Manchester, and that it did not have any information showing a “specific credible threat” to music venues in the U.S.