A Birmingham event hosted by BBC Radio 1Xtra was cancelled after rapper Krept suffered a slash wound in an assault backstage.
West Midlands Police were called to the show at the Arena Birmingham on Saturday night after the assault, which happened at around 10pm.
Officers said a man – who has been named on social media as rapper Krept – suffered a “slash wound” during the assault but had been treated by medical staff at the event and did not need hospital treatment.
The rapper, one half of the duo Krept & Konan was keen to reassure fans he was alright.
He tweeted: “My people thanks for the messages Im good, ill be back in no time. God was with me trust me. Cant keep a good man down.”
The lineup for the Arena Birmingham show also featured Wizkid, Aitch and DaniLeigh.
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.”
It added: “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.”