ROCK band Embrace had to cut short an illegal gig in London's Leicester Square after the police shut it down.
A crowd of more than 500 gathered to watch the Brighouse band, whose comeback single, Gravity, was released today.
Fans were tipped off about the show through a website.
They saw the group play a five-song acoustic set at the capital's landmark.
Opening track All You Good People immediately prompted a mass singalong.
Frontman Danny McNamara, 33, joked that any onlookers might mistake the crowd "for the premiere of The Village", which was showing at a nearby cinema.
Police ended the party when they arrived 20 minutes into the set.
One fan at the gig said: "The band heard a police siren so they legged it into a nearby radio station for shelter before they got arrested."
An official tour by the band gets under way at the Shepherd's Bush Empire in London on Friday.