THESSALONIKI, Greece (AP) — Thousands of police officers have been deployed to Greece's second-largest city ahead of anti-austerity protests at a trade fair where Prime Minister Alexis Tsipras is set to outline his post-bailout economic policy platform.

The Thessaloniki police department said more than 4,000 officers will be on duty in the northern city on Saturday as many previous protests turned violent.

U.S. personnel are helping with security since Commerce Secretary Wilbur Ross will be in Thessaloniki with American corporate delegations participating in the annual fair. The U.S. is the honored country this year.

Tsipras is due to meet Ross later Friday. He will inaugurate the fair on Saturday, delivering a keynote speech.

Trade unions, left-wing and anarchist groups plan protests around the fair venue, where right-wing groups also are set to rally.