Kneecap are an Irish-speaking rap trio who have courted controversy with their provocative lyrics and merchandise.

The investigation stems from alleged videos from a Kneecap gig where the rap trio apparently shouted, “Up Hamas, up Hezbollah.” Per the BBC, both militant groups are banned in the U.K. and expressing support for them is a crime.

British counter terrorism police Thursday launched an investigation into online videos of Irish rap group Kneecap after the band denied supporting Hamas and Hezbollah or inciting violence against UK politicians.