Riot police stormed two squats in the district of Koukaki in central Athens which had been re-occupied by anarchists earlier on Saturday.
The buildings, located on 45 Matrozou Street and 21 Panetolikou Street, had been cleared by riot police in a sweeping operation on December 18 last year, but anarchists returned by Saturday afternoon.
Anarchists threw bricks and paint at the officers who stormed the building at Matrozou Street.
Earlier nine people were held who came to demonstrate outside the buildings in support of the squatters.
The December raid at the building on Matrozou Street had drawn criticism over alleged police violence used against three residents of the adjacent house.
Police have denied any wrongdoing, saying officers had entered the neighboring building in order to gain access to the squat via its rooftop.