Danny Lim, best known for his colourful sandwich boards marked with political or social messages, was arrested in Barangaroo for offensive behaviour on Friday.

Niki Anstiss was on her way to get a coffee when the “absolutely disgusting” incident occurred. She said Mr Lim did “nothing wrong” but the police used "so much force" on the 74-year old.

Danny Lim was "screaming and crying" as he was arrested. Credit:Niki Anstiss

“Today I saw three police officers brutally rip his sign from his back and arrest him while he was screaming for them to not take his sign,” she said.

“It was the most spiteful act of bullying I have ever seen and NSW Police Force should be absolutely ashamed of themselves.