Three people are in a critical condition and one person has been arrested following a suspected crowd crush at a concert in south London.
Nigerian artist Asake said he was “praying” for those injured during the incident midway through his show at the O2 Academy Brixton on Thursday night.
In a statement outside Brixton police station on Friday afternoon, chief supt Colin Wingrove said an “urgent investigation” was under way.
He said one person had been arrested on suspicion of assaulting a police officer and that three people were in a critical condition in hospital following the incident, down from four reported by the force earlier on Friday.
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Mr Wingrove also said an incident in which an officer was “apparently seen to push a member of the public” is currently under review by the force’s director of professional standards.
A total of eight people were taken to hospital after a crowd attempted to gain entry without tickets, the Metropolitan Police previously confirmed.
Two who were less seriously injured were treated at the scene.
Asake, whose real name is Ahmed Ololade, said in a statement on Instagram: “My heart is with those who were injured last night and caused any form of discomfort. I pray you get well soonest.
“I am also in the process of reaching out to individuals.
“I still do not have the full brief from the venue management themselves as to what led to the disruption at the entrance of the Brixton Academy, but we are thankful that all was peaceful at the end.
“For my people who enjoyed the beginning of my performance, I am sorry that it was cut short.
“Thank you for your unbelievable love, London. I love you too much! I’m looking forward to seeing you again in a bit!”
Before the gig, he had posted on Twitter asking fans not to come to the venue unless they had a valid ticket.
Footage posted online showed large crowds outside the building on Thursday night, with many people holding up mobile phones and filming the scene.
In other video content, the crowd inside the venue could be heard booing when an announcement was made from the stage saying the show was being stopped.
Lambeth police previously said emergency services attended the venue in Stockwell Road following reports shortly after 9.30pm of injuries after “a large crowd attempted to gain entry without tickets”.
Scotland Yard said police officers, London Ambulance Service and London Fire Brigade attended the scene and found “a number of people with injuries believed to have been caused by crushing”.
Mayor of London Sadiq Khan tweeted that his “thoughts are with all those affected by the awful incident at Brixton Academy”. – PA