The leader of a right-wing group was busted by Portland, Oregon, police Friday night before a rally expected to draw people from around the country.

Patriot Prayer’s Joey Gibson to urge his followers to “show up one hundred-fold” in response to his arrest, the Associated Press reported.

The arrests of Gibson and five other far-right activists appear to be a signal from cops to organizers to keep their event peaceful, the AP said. Anti-fascist groups have promised to confront the right-wingers at their rally in Oregon’s largest city. Similar events in the past resulted in widespread unrest on Portland’s streets.

An organizer told the Portland Oregonian he expects up to 1,000 people to take part in the demonstration. Thousands of counter-protesters are also expected.

Gibson was not involved in planning Saturday’s event but organized similar rallies the past two years that erupted in clashes, He surrendered Friday on an arrest warrant for rioting related to a May 1 confrontation with Antifa activists outside a bar in Portland.