It was learned that Police showed up at the concert on Thursday night and asked that the event be abandoned part-way through.
Among the eight people who were hurt during Nigerian singer, Ahmed Ololade, known professionally as Asake’s concert at the Brixton O2 Academy in south London, at least four have been identified as being in severe condition.
It was learned that Police showed up at the concert on Thursday night and asked that the event be abandoned part-way through.
A sizable throng was seen gathering outside the venue in viral videos from the event that were posted on social media.
People were screaming, shouting, and struggling as they stretched from the road outside to the venue's doors.
A video shot outside the Academy shows crowds on a side street, with a woman heard saying that people are pushing each other.
According to an eyewitness, it was learned that more than 1,000 people had turned up for the concert without tickets.
It was the third of three sold-out shows at the Academy by the Nigerian singer, also known as Mr Money.
Before the show, Asake asked fans on Twitter not to try to get in unless they had a ticket.
After being discharged from St Thomas' Hospital with suspected internal bleeding, one of the injured persons spoke to the BBC News.
The woman, from Battersea in south London, said: "I was just queuing up to give them my ticket and then the crowd out here was insane, they just came and pushed and I just fell down.
"I was trying to get up, people were stepping on my head, all over me. I had more than 10 people on top of me."
She described her fear as she lay on the ground, saying, "I couldn't breathe and I completely passed out. I thought I was dead.
"I took my last breath and I could not get any more oxygen. I was so scared.
"A man pulled me out so when I woke up, I was in the back of the ambulance. I'm just so grateful."
John, 32, who lives next to the O2, also told BBC News: "I saw everyone at the front door of Brixton Academy, [then] everything just stopped.
"It looked like the gig had been cancelled, and then some commotion, some pushing and shoving, and the police came shortly after. That's when it kicked off and became aggressive.
"People at the front of the Brixton Academy were really pushing and shoving and trying to break through the door and force their way in," he added. "The glass of the doors was broken."
Journalist and author Jason Okundaye, who was also outside the venue at the time, said "there was absolutely zero communication" from Academy staff.
He added that he went home after observing the dangerous conditions, saying: "Outside the venue was so unsafe, still slippery conditions because of the earlier snowstorm, freezing cold, a confused crowd and aggressive police dogs making the risk of a huge crush likely."
According to its website, the O2 Academy Brixton has a standing capacity of nearly 5,000 people.
The venue is directly across the street from Brixton police station, which explains the quick response on Thursday night.
Mayor of London Sadiq Khan tweeted to say he was "heartbroken".
"My thoughts are with all those affected by the awful incident at Brixton Academy," Mr Khan added.