Political activist Ciaron O’Reilly has faced court in Brisbane after breaching his G20 ban on Saturday.
He was slapped with an exclusion notice on Thursday, barring him from the G20 security zone.
O’Reilly was arrested by police near Musgrave Park around 3pm (AEST).
“In less than two minutes, an unmarked car pulled up and two plain clothes detectives came out and had this standing order,” Mr O’Reilly told ABC News.
“I think it is an outrageous infringement of my civil rights.”
He told officers he wanted to speak to US President Barack Obama about freeing Chelsea Manning, the US soldier imprisoned for leaking confidential documents to WikiLeaks.
He also shouted “Free Julian Assange!” before being taken away in a police van.
O’Reilly describes himself as a non-violent, anti-war protester.
He was previously jailed in the United States after breaking into a military base in New York.
His case has been adjourned until December four.