Some 4,000 police officers, including motorcycle patrols and two helicopters, have been assigned to guard the Thessaloniki International Fair (TIF), which opens Saturday with a keynote address by Prime Minister Antonis Samaras.

Security is expected to be tight at the event, which is expected to attract thousands of people protesting austerity measures.

A number of marches have already been organized, and will start Friday afternoon and culminate Saturday evening.

Streets will be closed around the Thessaloniki Convention Center, which is hosting the TIF, while parking is also prohibited in the vicinity from 6 p.m. Friday until 3 p.m. on Sunday.