Three boats carrying 202 people including four Sri Lankan migrants had been sent to Turkey from Greece on Monday under a controversial deal signed between the EU and Turkey, the CNN reported.
Greek authorities said there were 136 migrants on board the two boats from Lesbos -- the majority of them from Pakistan with others from Sri Lanka, Bangladesh and India as well as two Syrians who had returned voluntarily.
They said 66 migrants on board the boat from Chios included 42 Afghans.
According to Greek officials, the migrants had not applied for asylum. A Turkish official said Turkey has agreed to accept up to 500 migrants per day.
These migrants are the first to be deported under the auspices of a controversial "one in, one out" deal struck between the European Union (EU) and Turkey last month.
Under the terms of the deal, anyone who crosses into Greece illegally after March 20 will be sent back to Turkey.
For every Syrian sent back to Turkey, a vetted Syrian refugee will go from Turkey to Europe to be resettled, although the maximum number is capped at 72,000 people.
In return, the EU will give Turkey billions in funding to help it provide for the migrants within its borders, and grant various political concessions.
The plan was agreed upon last month as Europe struggles to respond to the largest migration crisis since World War II. More than 1 million people made "irregular arrivals" inside Europe's borders in 2015 alone, many of them displaced by the Syrian civil war.
The new rules may divert the thousands fleeing their home countries farther west to nations such as Italy.