More than 140 people, mainly migrants, were arrested in dawn raids on Athens squats Monday as part of a major crackdown, police said.
Dozens of officers cleared four squats occupied for several weeks, mainly by refugees and migrants, in the Exarcheia district of Athens.
Athens prosecutors authorised the raids after complaints filed by the owners of the buildings being squatted.
A police source said 143 people, some without papers, had been picked up. Most were from Afghanistan, Eritrea, Iran and Iraq.
There were 57 men and 51 women in the group, and the rest were children, the source added.
The new conservative government of Kyriakos Mitsotakis has vowed to bring "order" to the district, promising regular police patrols.
Two Greeks and a Frenchman were detained for disturbing the peace.
The Exarcheia neighbourhood has frequently been the site of clashes between anarchists and police, particularly since 2008, when a police officer shot dead a teenager, sparking days of rioting.
The new mayor of Athens, who was sworn in on Sunday, has pledged to make security his top priority.
Costas Bakoyannis has accused the previous leftist government of having taken a soft line against vandalism carried out by some anarchist groups.