A Brisbane Greens councillor has been arrested while protesting in the CBD at a weapons expo.

Jonathan Sriranganathan was protesting outside the Land Forces International Land Defence Exposition in South Brisbane this morning.

He was one of four arrested.

It’s alleged he entered a restricted area without accreditation, and was asked to leave by police.

In a post on social media, he wrote that it was a peaceful protest at the “killing machines expo”.

He said he was told he was trespassing, despite standing on a footpath outside the expo.

“Today, I was standing on public land, on a publicly accessible footpath outside the convention centre, participating in an authorised peaceful assembly,” he wrote.

He was charged with one count of trespass and obstruct police, and was released on bail.

Image: Nine News