Greece has illegally sent back more than 5,000 refugees to Turkey's shores over the last six months, Turkish officials said.
Ankara said the move violated a readmission agreement between the two countries and the burden of refugees should not be shouldered by Turkey alone but by all European countries.
Many of those who were returned have been taken to an immigration facility in the Turkish border town of Edirne.
They said Greek police abused them and forced them onto boats.
TRT World's Kilmeny Duchardt has more details.