When the deadly blast struck Manchester Arena at around 10:30pm last night (22 May), many thought that the bang was caused by balloons popping.
"It sounded like a big balloon popping," teenager Sammy said in a Periscope video. "But it was kind of muffled, like it wasn't in the stadium itself."
He described the aftermath of the explosion like "a scene from a horror movie."
"The whole arena literally split like the Red Sea – everyone was trampling over each other, sprinting to get to the nearest exit," he said.
The explosion rocked the neighbourhood, with eyewitnesses reporting smoke pouring out of the arena entrance.
Suzy Mitchell, who lives in a flat opposite the venue, said she heard a "huge bang" while lying in bed. "The bang was so big I heard it from my room which is at the back of the apartment blocks," she said.
Young fans and their parents said that "absolute panic" set in when the bomb went off near the entrance of the venue.
"People were dropping to the floor and thought there might be a gunman in there," Anne-Marie, who was at the concert with her 13-year-old daughter, told BBC 5 Live.
17-year-old Oliver Jones, who attended the concert with his sister, described the chaos that followed the blast. "I saw people running towards one direction and then many were turning back to run the other way. Security was running out as well as fans and other concertgoers," he said.
Rachel told BBC Radio Manchester that she grabbed her 14-year-old daughter and ran as soon as she heard the explosion. She said that, as they turned the corner, they saw a "horrific stampede of people coming down the steps and people being crushed on the floor."
The bomb went off metres in front of Abby Mullen. She described the horror scene she witnessed in Facebook post. She said people's skin, blood and faeces were everywhere "including in my hair and on my bag".
She shared several images of her blood-spattered hair and bag alongside the post. "I understand these images might be upsetting," she wrote. "However, I feel as though need to be shown just how cruel this world really is."