The attack at the Ariana Grande concert at Manchester Arena saw 22 killed and more than 800 injured. Suicide bomber, Salman Ramadan Abedi was killed instantly.
The last strains of Ariana Grande's song Dangerous Woman had just faded. The singer stepped behind the curtains. The lights came up. Pink balloons and girlish chatter floated through the air as people began to file out of the Manchester Arena, just past 10.30pm.
Then the unthinkable happened. An orange flash, and a huge bang, as a male suicide bomber detonated what police believe was an improvised explosive device in the foyer area between the arena and the neighbouring Victoria train station.
Witnesses described being knocked off their feet by a huge explosion. One described an orange flash; another spoke of nuts and bolts tearing into young concert-goers.
Then the air filled with screams, as thousands of fans - mostly young girls - turned and ran, some covered in blood.
Horrifying footage showed terrified children leaping over chairs and barriers, with people being trampled as they desperately tried to escape the 21,000-seat venue on Monday night local time.
At least 22 people - mainly children and teenagers - were killed in the blast, police said. Last night they named Georgina Callander, 16, as one of the victims.
Another 59 injured were taken to eight hospitals around Manchester and many more "walking wounded" were treated at the scene, some with shrapnel wounds, the local NorthWest Ambulance service said.
Jenny Brewster said she was leaving the concert with her 11-year-old daughter when the blast hit.
"As I turned around, boom, one loud noise," she told Sky News. "A gentleman said, 'run!' so we ran."
Outside "you could smell the burning", she said.
Young victims, look visibly distressed as they leave the Park Inn hotel that took-in victims from the Manchester Arena stadium in Manchester. Photo / Getty Images
A 17-year-old girl told the Manchester Evening News the explosion happened right in front of her.
"I remember seeing orange. Everyone started crying and running away. I could see people near me and I saw a torso."
Ryan Morrison, 19, heard the explosion from behind. Then someone shouted "bomb".
"Everyone started running. It was carnage. People were injured by being trampled as they tried to get out."
Sirens filled the air as first responders - including 60 ambulances - rushed to the scene. Armed officers surrounded the venue and bloodied casualties were stretchered out of the concert while others staggered out, bleeding.
Word started spreading on Twitter and Facebook. Desperate families and friends posted names and pictures of their loved ones, pleading for a phone call.
But many had dropped their phones in the hurry to escape. Parents spent a long night waiting to hear what had happened to their children.
Nearby Victoria Station was evacuated and all trains in and out suspended, leaving many stranded. Mancunians stepped up to help, with offers of free taxi rides, bus rides, hotel rooms and food.
One woman, Paula Robinson, shepherded around 50 unaccompanied children to a nearby hotel and posted her number on social media for worried parents to call. Last night she still had more than 30 children in her care.
Grande, 23, was uninjured. She tweeted that she was "broken" in the hours after the explosion.
"From the bottom of my heart, I am so so sorry. I don't have words," the pop singer said.
Police in the northern English city confirmed last night that children were among the dead.
Police are treating the bomb as a terrorist attack, although at the time of going to press no one had claimed responsibility. If confirmed as terrorism, it will be the worst terrorist attack in the UK since the 2005 London bombings, when 56 people were killed.
Greater Manchester Police Chief Constable Ian Hopkins said the bomber was killed in the blast. More than 400 police officers were involved in the investigation, Hopkins said.
Their priority was working out whether the bomber was a lone wolf or acting as part of a network.
Image 1 of 14: Armed police work at Manchester Arena after reports of an explosion at the venue during an Ariana Grande gig in Manchester. Photo / AP
The country was already on a severe international terror alert prior to the attack. London police last night evacuated the Victoria Coach Station and cordoned off streets around Buckingham Palace, reportedly after a suspicious package was found.
Prime Minister Theresa May was chairing an emergency meeting the morning after the incident. She said her thoughts were with the victims and families of those affected.
Campaigning for Britain's June 8 election has been suspended.
Reuters reported countries worldwide were reviewing security procedures for major public events such as concerts and sports games.
Condolences have come in from leaders around the world.
US President Donald Trump said all nations must band together to stamp out radicalism. Those responsible for the attack were "evil losers".
Prime Minister Bill English called the event an "awful tragedy".
"It is devastating for parents if their young ones go off to entertainment - no one expects them to lose their lives in such a cruel and unpredictable way."
