The activists began occupying Paradeplatz Square and Bahnhofstrasse Street at about 6.00 a.m. (04:00 GMT), the police said.
By noon, police had taken about 30 people into temporary custody.
"A total of 83 people (47 women and 36 men) were taken to police stations," the statement read.
The police added that the case would be handed over to the Zurich Prosecutor's Office.