THESSALONIKI, Greece (AP) — The Latest on an international trade fair in Greece: (all times local):

7:50 p.m.

Greek police say tear gas and stun grenades have been used to keep thousands of protesters from reaching a venue where Prime Minister Alexis Tsipras is due to give a keynote address on the economy.

The crowd of about 6,000 gathered Saturday to protest an agreement Greece signed with neighboring Macedonia to end their long name dispute.

Officers kept the protesters at bay, but the group approached the fairgrounds from another direction and attacked officers with rocks and others items.

Three more protest marches are headed to the Thessaloniki International Exhibition Centre. Police let about 6,000 participants in a union-backed march by without incident.

12:55 p.m.

U.S. Commerce Secretary Wilbur Ross has inaugurated a trade fair in recession-weary Greece, where the government is pushing for overseas investment but faces mass protests after years of plummeting living standards.

Ross joined Greek Prime Minister Alexis Tsipras Saturday at the opening of the annual trade fair. The United States is the featured country at this year's event, and Ross traveled with a delegation of executives from dozens of major U.S. companies.

Greece last month ended its third consecutive international bailout and now must return to markets that have been rattled by financial concerns in nearby Italy.

Some 4,000 police officers are on duty in the northern Greek city as several major protest rallies are planned later Saturday, led by labor unions.