At least 22 people, including children, have been killed in a suspected terror attack at an Ariana Grande concert in Manchester.

At time of writing, 59 people were being treated for injuries from the blast, which has been dubbed “the most deadly attack in Britain in a decade” and labelled by police as a “suicide” attack.

Home Secretary Amber Rudd described it as “a barbaric attack, deliberately targeting some of the most vulnerable in society”.

British Transport Police said the explosion – which happened at 10.35pm, shortly after the concert came to a close – was in the arena's foyer, which connects with Victoria train and tram station, a major hub on the northern edge of the city centre.

Reports say some initially thought that the loud bang, moments after a score of pink balloons were released into the audience and the lights had come up following a final encore, could somehow have been part of the show’s finale.

Grande’s fanbase is largely children and teenage girls, and a number of young people became separated from their parents in the chaos, with many parents waiting outside the venue to pick up the, up after the concert.

Manchester Arena blast: at least 22 dead and more than 50 injured in suspected terror attack