Police are interviewing a group of men who allegedly climbed onto the roof of a Townsville shopping centre and waved a racist sign in response to the Sydney siege.

Officers were called after the group were spotted on the roof of the Willows Shopping Centre about 3.15pm Monday.

Men stood on top of a Townsville shopping centre holding a racist sign in the wake of the Sydney siege. Credit:Facebook

A photo of the four men holding up a cardboard sign with the words: "DEATH TO ISIS. GET OUT YOU RAG-HEADED F---S. ANTI-TERROR" has emerged on social media.