The rapper known as Tekashi 6ix9ine is in custody and awaiting a Manhattan court appearance, federal authorities told the Associated Press.
The Brooklyn-based rapper, whose legal name is Daniel Hernandez, is among four people arrested on racketeering and firearms charges.
The authorities also arrested three of Hernandez's former associates.
An attorney who has previously represented Hernandez did not immediately respond to an email seeking comment Monday.
6ix9ine has been among the most ascendant and controversial names in hip-hop in recent months. His debut album, Day69, is among the most downloaded records on iTunes.
But he's had several run-ins with law enforcement. He recently pleaded guilty to disorderly conduct in Brooklyn Criminal Court in connection with a May traffic stop.