A second group of migrants was set to be returned to Turkey on Friday under the terms of an EU-Turkey deal aimed at curbing migration movements.
Four buses brought 45 migrants to the main port on the island of Lesbos. They were to be transferred to a boat heading to the Turkish port of Dikili, state radio station ERT reported.
Another vessel was heading to Lesbos carrying a further 95 migrants destined for Turkey, state-run television reported.
Those being taken to Turkey on Friday had not made applications for asylum, the reports said.
Activists have protested against what they described as the "deportation" of the migrants, which began earlier this week.
On Monday, more than 200 migrants from Lesbos and Chios were taken to Dikili under the terms of the European migration deal with Turkey.
The agreement seeks to put an end to a migration influx that saw more than 1 million people reach Europe last year. Most of them came via Turkey to Greece, undertaking dangerous sea journeys that not all survived.
On Thursday, about 250 migrants and refugees broke out of a reception centre on the Greek island of Samos, reports said.
They marched through the streets of Vathy, the island's main town, demanding that they be allowed to continue their journey to the European mainland, and not be taken to Turkey, under the terms of a European deal.
Eyewitnesses described how some migrants were carrying knives and threatening security forces.
Police and local authorities from the European border agency Frontex convinced most of the migrants to return to the reception camp, local radio reports said early Friday.
Migrants from Pakistan and Afghanistan stand near a chain-link fence at a detention center in Lesbos. (AFP/Aris Messinis)
