A number of people have been injured and a major incident declared after a series of stabbings in Birmingham.
Police and paramedics were called to reports of a knife attack in the early hours of Sunday, with further stabbings then being reported.
One witness told BBC Radio 5 Live that the attack seemed like “one group of boys against another group of boys”.
West Midlands Police said there were “a number” of victims, but the severity of their injuries was not immediately known.
Eye-witnesses reported as many as eight people were injured following the disorder in the city overnight.
Police denied reports of gunshots being fired, and added “it would not be appropriate to speculate on the causes of the incident”.
A witness, Cara, told 5 Live she had heard racial slurs during the incident, adding that it was a “multicultural night” in the clubs near the Arcadian Centre.
She added: “They were not just having an argument and then fighting, it was straight into fists being thrown. There was not much talking going on.
“Drinks were being dropped, bottles that they had obviously bought in the club, rings were falling off so jewellery was going everywhere, clothes were being torn.
“One of the males actually ended up with his hair being pulled out and left with a bald patch.”
The Arcadian venue, located around five minutes’ walk from Birmingham New Street station, is a hub of restaurants, bars, cafes, clubs and hotels.
Featuring an open air central piazza, it is close to the city’s Chinese Quarter and Gay Village areas.
The majority of Hurst Street, which runs past the Arcadian, has been taped off by police on Sunday morning, in an area which had already been closed off to traffic to aid social distancing.
Several yellow police evidence markers could be seen on the ground, some near to broken glass.
Two forensic tents had also been sited in nearby Irving Street, close to the gates of a primary school.
Police said the response would be ongoing “for some time” and urged people to stay away from the area.
The force added: “We are aware of a number of injured people, but at the moment we are not in a position to say how many or how serious.
“However, all emergency services are working together at the scene, and making sure that those who are injured receive medical care.
“Work is still going on to establish what has happened, and could take some time before we are in a position to confirm anything.”
Foreign Secretary Dominic Raab said those in the vicinity of the major incident in Birmingham should be “very vigilant”.
Speaking to Sky News’ Sophy Ridge On Sunday programme, Mr Raab said: “My thoughts are with the victims and their families, there is obviously an ongoing police investigation.
“I can’t say too much more at this stage but people should be very vigilant if they are in that area.”
West Midlands mayor Andy Street said police were set to hold a press conference on Sunday morning.
Writing on Twitter he said his thoughts are with those affected by the incident and asked people not to speculate about it.
“The city remains open for business as usual this morning but clearly people are asked to avoid the immediate area surrounding Hurst Street while police carry out their investigation,” Mr Street tweeted.