BBC Radio 1Xtra Live was called off on Saturday after a man – believed to be rapper Krept – was slashed backstage.
The show was underway at the Arena Birmingham when West Midlands Police were alerted to an assault in the backstage area by security at the venue.
Officers said the victim suffered a slash wound, but did not need hospital treatment.
The man was unnamed by police, however the victim is believed to be 29-year-old Casyo Johnson, one half of duo Krept and Konan.
The musician tweeted this morning: “I’m good, I’ll be back in no time.”
Thousands of people with tickets to the sold out show, which featured Wizkid, Aitch and DaniLeigh among the lineup, were forced to leave early as the event came to an abrupt end.
A statement from BBC Radio 1 said: “Following an isolated serious incident, we have had to stop 1Xtra Live in Birmingham.
“We are co-operating fully with the police to establish what has happened.”
In a further statement, it said: “We’re sorry to everyone who attended 1Xtra Live in Birmingham for the early finish; however, the health and safety of everyone involved is always our top priority.
“We are upset and saddened that something like this should happen to a guest at one of our events and we remain in close contact and continue to offer our full support.”