Suicide bomb attack in Manchester pop concert leaves 22 dead

The youngest of those killed in the attack was confirmed to be just eight years old, with teenagers thought to be among the other dead, as a massive bomb exploded in the foyer of the venue at around 10:30pm.

A dozen children under the age of 16 were among the 59 injured, according to the North West Ambulance Service, with paramedics saying they had treated "shrapnel-like injuries".

Greater Manchester police said just before noon on Tuesday that they had arrested a 23-year-old man in South Manchester in connection to the attack.

Speaking in front of 10 Downing Street on Tuesday, Prime Minister Theresa May referred to the incident as a "callous terrorist attack", and said that security forces were working to establish a clearer picture of what happened.

"It is now beyond doubt that the people of Manchester and of this country have fallen victim to a callous terrorist attack, an attack that targeted some of the youngest people in our society with cold calculation," May said.

"This was among the worst terrorist incidents we have ever experienced in the United Kingdom."

May also praised the work of the emergency services in the immediate aftermath of the incident, saying that the "cowardice of the attacker was met by the bravery of the emergency services and the people of Manchester."

Campaigning for the UK's general election has been suspended by all parties as a result of the attack.

LONE WOLF OR NETWORK?

Greater Manchester police asked members of the public to avoid the area on Tuesday as they continue work at the scene.

Chief constable Ian Hopkins on Tuesday morning confirmed the death toll had risen from 19 to 22.

"We have been treating this as a terrorist incident and we believe that while the attack last night was conducted by one man, the priority is to establish whether he was acting alone or as part of a network," said .

"The attacker, I can confirm, died at the arena. We believe the attacker was carrying an improvised explosive device, which he detonated, causing this atrocity.

"We would ask people not to speculate on his details or to share names. There is a complex and wide-ranging investigation under way."

The explosion is the worst such attack in Britain since the 2005 London bombings when 52 people were killed by suicide-bomb explosions on the transport network.