Hundreds of people at a major music awards show were being quizzed today after a triple stabbing left one guest seriously injured and two others wounded.
There were chaotic scenes after the violence erupted at last night's 6th Annual Urban Music Awards at The O2 Arena in London, forcing organisers to abandon the ceremony after an hour and a half.
Eyewitnesses spoke of seeing "blood all over the floor" after a huge brawl broke out at around 10pm, sending champagne bottles and chairs flying and causing general "hysteria". Guns were also said to have been spotted inside the auditorium.
Around 300 guests ended up being stuck inside the venue until the early hours while police blocked the exits and questioned people one by one before allowing them out.
One man was arrested.
Guest Andre Nevling, 24, said a woman sitting at the same table as himself was "covered" in blood.
"Obviously the guy who got stabbed must have run straight past her and she's pretty shaken up.
"I came out of the auditorium and looked at her and she was just standing there. I saw blood all over the floor and then I was like, 'Jesus you're covered in it'," he said.
Another eyewitness, who wanted to remain anonymous, said: "I didn't see what happened but there were champagne bottles flying and I hid under the table."
Emma Fairclough, 33, also from London, said she heard there were guns inside the arena. "I have spoken to two people who said they have seen guns in the arena this evening," she said.
The awards were held in the indigO2, a 2,350 capacity venue inside The O2 Arena.
Dozens of police arrived after 10pm and cordoned off an area covering approximately six tables inside the auditorium.
London Ambulance Service said three patients, one of whom is thought to be a 20-year-old, were treated at the scene and were been taken to London hospitals.
Police eventually put a cordon in place outside the arena. Witnesses spoke of a "corridor of police" made up of at least 25 officers outside a side entrance through which people at the event were allowed to leave one at a time.
Mike Muller, 38, from London, said: "(The police) locked the place down and to get out I have been questioned three times by three different officers."
He added: "I was on the table right next to where it happened - it was general confusion, hysteria."
Guests also spoke of light security arrangements at last night's event.
Natalie Williams, 32, said: "There was no security, nothing. Before anything even happened I commented to my boyfriend, because we live nearby and come here a lot, and we usually get screened coming into the building. Tonight there was nothing."
Mark Hudson, 28 and from London, added: "There's a reputation with these events that people carry knives. But there were no searches, no nothing. I was worried about this before I came here."
Of the mayhem, he said: "It was a big brawl, I would guess about 25 or 30 people, with chairs being thrown."
Estelle, Adele, Leona Lewis, Dizzee Rascal and Duffy were among the performers nominated for awards at last night's ceremony.
Singer Estelle, 28, was nominated for five awards while the soul singer-turned What Not To Wear presenter Mica Paris was to be presented with a Lifetime Achievement Award.
Last year saw the launch of the Urban Music Awards USA in New York and in April the Caribbean Urban Music Awards were launched in Jamaica.