Arrivals in Greece of migrants crossing by sea from Turkey fell sharply on Wednesday, three days after an agreement came into force to seal off a route used by hundreds of thousands of people fleeing conflict in the past year.
New arrivals on the Greek islands facing Turkey dropped to 68 in the 24 hours to Wednesday morning from 225 the previous day, data from the migration ministry showed.
It was unclear if the decline was directly related to the accord.
"We had a very low influx from the other side of the Aegean... which we consider positive," said George Kyritsis, a government spokesman on the refugee crisis.
Under the accord brokered last month between the European Union and Ankara, migrants and refugees who use irregular sea crossings in the Aegean to get into Greece are being sent back to Turkey.
In return, the EU says will take in thousands of Syrian refugees directly from Turkey and reward it with financial aid, visa-free travel and progress in its EU membership negotiations.
Human rights campaigners say the accord is a sham that runs roughshod over people displaced by war.
Since the deal was implemented on Monday 202 people, the vast majority from Pakistan, have been returned from Greece, according to authorities in Athens.
Kyritsis told Greek state TV more people could be returned later this week.
"It is possible... We are interested in two things. Sticking to the deal, and maintaining the rights [of migrants and refugees]… It is a delicate and complicated process, we don't want to make mistakes," he said.
Greece has reported a spike in the number of asylum applications of individuals who have arrived since March 20, the date the first phase of the EU accord took effect and new arrivals were detained in holding centers.
Under a newly-introduced Greek law, an asylum applications process within the detention centers, which includes a recourse to appeal, lasts about nine days. [Reuters]