At least 22 people are dead and dozens more injured in a terrorist attack at the end of a concert by US singer Ariana Grande in the English city of Manchester, according to Greater Manchester Police.
There were children among the 22 people killed in the attack, and 59 more were injured, Greater Manchester Police chief Ian Hopkins said early on Tuesday.
The man behind the attack died when he detonated his device, Hopkins said, adding that the suspect had set off an "improvised explosive device" as the audience was leaving the concert on Monday night.
"We believe, at this stage, the attack last night was conducted by one man," Hopkins told reporters. "The priority is to establish whether he was acting alone or as part of a network."
"We believe the attacker was carrying an improvised explosive device which he detonated causing this atrocity," he said.
British police said on Tuesday they had arrested a 23-year-old man in connection with the attack.
"With regards to the ongoing investigation into last night's horrific attack at the Manchester Arena, we can confirm we have arrested a 23-year-old man in South Manchester," police said in a statement.
British Prime Minister Theresa May earlier said the incident was being treated as a terrorist attack.
The explosion rocked the place when concertgoers were beginning to leave the arena, which has the capacity to hold 21,000 people, after Grande's closing set, shortly after 10:35 pm (2135 GMT) at the arena. A large number of children were also attending the event.
According to witness accounts, a huge bang was heard from inside the arena causing panic and sudden rush in big crowds. Police has surrounded the Victoria train station.
"We were making our way out and when we were right by the door there was a massive explosion and everybody was screaming," a witness said. "It was a huge explosion - you could feel it in your chest. It was chaotic. Everybody was running and screaming and just trying to get out of the area."
Emergency services were also found to be heading to the area. The police have confirmed fatalities without giving further details.
May will suspend election campaign
British Prime Minister May described the attack as “appalling,” and said her thoughts are with the victims of the Manchester’s arena.
According to a report, May will suspend her general election campaign in the wake of the Manchester attack.
The prime minister will stop campaigning for the June 8 election, BBC reported.
"We are working to establish the full details of what is being treated by the police as an appalling terrorist attack,” May said in a statement.