Manchester Arena Explosion: What we know so far

The Greater Manchester Police Department reported via Twitter that the agency is treating the incident as a terror attack until proven otherwise.

The crowd was made up of mainly young people who had come to see Grande in her first of three scheduled concerts in the United Kingdom, on her European and Latin American tour.

Videos posted on Twitter showed concertgoers running and screaming from their seats.

"It was mayhem on the street, there were children crying, trying to get in touch with parents, parents on their phones trying to contact their kids", she said, adding that cell connection was poor as so many people were using their phones simultaneously.

The Dangerous Woman tour is the third concert tour by 23-year-old Grande and supports her third studio album, "Dangerous Woman".

Abby Barker, who attended the concert, told ABC News that Grande had just left the stage when there was a loud bang. "We ask all of you to hold the victims, their families, and all those affected in your hearts and prayers".

Sheffield concertgoer Karen Ford said they heard a huge bang just after the concert finished and they were making their way outside, where her husband was waiting to drive them home. If the incident is confirmed to be a terrorist attack then it would be declared one of the deadliest attacks on Britain since 2005.

Reuters reported that a suicide bomber is believed to have been behind the attack, citing two USA officials.

"In the absence of conclusive evidence, the choice of venue, the timing and the mode of attack all suggest this was terrorism", said a USA counter terrorism official who also spoke on condition of anonymity.

In the wake of the attack, concerned loved ones shared photos of their missing friends and family members on social media, in the hope of receiving information.

Britain's terrorist threat level stands at "severe", the second-highest rung on a five-point scale, meaning an attack is highly likely.

As people scrambled for answers, police advised to follow their twitter account for further updates. He was shot dead at the scene.

Police departments in the US, including Chicago, are monitoring the Manchester situation.

On Facebook, Manchester Arena confirmed the incident and stated it "occurred outside the venue in public space". When he awoke, he said he saw many casualties around him.

"No trains or trams are running from Manchester Victoria station".

A spokesman for Ariana Grande told media the songstress was safe.

Ms Entwhistle said she and other volunteers had taken in "between 60 to a hundred children". She said her phone had not stopped ringing since her tweet.

  • Jon Douglas