Young children are among 22 people confirmed dead and 59 injured in a suspected suicide attack at Manchester Arena.
The explosion was heard just after 10.30pm last night at the end of a concert by the US singer Ariana Grande.
A lone male attacker, who died in the blast, was carrying an improvised explosive device which he detonated, according to Greater Manchester Police.
Police have set up an emergency telephone number in response to the attack: 0161 856 9400.
The blast occurred shortly after Ariana Grande had left the stage at the arena – the city’s largest indoor venue with a concert capacity of about 21,000.
The explosion took place close to the entrance to Victoria train and tram station. The station has been closed and all trains cancelled.
Prime minister Theresa May was chairing a meeting of the government’s emergency Cobra committee this morning.
Political parties have suspended general election campaigning.
Short breaks specialist SuperBreak – which offers hotel packages across the UK as well as in Europe – said its thoughts were also for “those people who lost their lives or were injured in the events last night in Manchester”.
The company said any agents with clients due to travel in the Manchester area in the next few days who have concerns about their plans should contact its call centre to discuss arrangements.