ASAP Rocky has been arrested in Sweden and accused of aggravated assault.
Prosecutors say it's to do with a fight on Sunday in the capital Stockholm, where he'd been playing at a festival called Smash.
A video, since published online, appears to show him punching another man in the street.
But the rapper has also put videos of his own up on social media. He says they're from before the fight and they show the man following him.
Sweden's Prosecution Authority says ASAP Rocky, real name Rakim Mayers, is one of four people who've been arrested.
Of the other three, two are suspected of aggravated assault and one of assault.
In the videos on ASAP Rocky's Instagram, he and the people he's with repeatedly tell a pair of men to stop following them.
One of the men, though, accuses the rapper's team of breaking his headphones.
In the caption for the first video ASAP Rocky writes: "We don't know these guys and we didn't want trouble. They followed us for four blocks".
In the second, he accuses the man of hitting his security guard "in the face with headphones".
News agency AFP is reporting that the authorities have until Saturday to decide whether to formally take action.
That's the day before ASAP Rocky is due to headline Wireless Festival in London.
Newsbeat has asked him for a statement, but he hasn't yet got back to us.