Greece on Friday expelled a second batch of migrants to Turkey under a controversial EU deal criticised by rights groups, an AFP stringer witnessed.
The 45 migrants, who a police source said were all Pakistani nationals, departed from the island of Lesvos on the Turkish ferry Lesvos.
Three activists were arrested after clinging onto the ferry's anchor to prevent it from leaving.
Another 30 people gathered at the port of Lesvos, chanting “Stop deportations”, “EU shame on you” and “Freedom for the refugees”.
Another group of around 80 migrants is expected to leave Lesvos later in the day.
According to the Greek government, the operation concerns people who have not requested asylum in Greece.
”Whoever applies for asylum is removed from the list,” a government source told AFP.
A first batch of 202 migrants were sent to Turkey from the islands of Lesvos and Chios on Monday, sparking a flurry of asylum demands and forcing Greek authorities to delay further expulsions as they have to examine the demands individually.
Greek officials now expect a two-week delay while authorities examine the first of those asylum applications.
Fear of deportation has prompted acts of desperation in some of the camps where migrants are held.
On Thursday, some 150 migrants broke out of a camp on the island of Samos but were later persuaded to return, the government source said.
A similar incident occurred on the island of Chios last week.
Dozens of migrants on Samos and Lesvos also claim to have begun a hunger strike to prevent their expulsion and demand the reopening of borders shut by Balkan nations last month.
One Pakistani hunger striker collapsed in Moria, the main camp on Lesbos, and was taken for treatment by medical charity Medecins du Monde.
Another Pakistani on Samos, named Ali, told AFP that a dozen of his countrymen were on hunger strike there.
“They told us to apply for asylum in Greece and that if not, we are going to be sent back to Turkey.
“We risked our lives to come here, we don't want to go back to Turkey because they are going to send us back to Pakistan. We don't want to apply for asylum in Greece, we want to go to Germany,” Ali said.
Under the terms of the EU-Turkey deal, all “irregular migrants” arriving on the Greek islands from Turkey since March 20 face being sent back, although the accord calls for each case to be examined individually.
And for every Syrian refugee returned, another Syrian refugee will be resettled from Turkey to the EU, with numbers capped at 72,000.
In return, Turkey is slated to receive benefits including visa-free travel for its citizens to Europe, which in the accord is promised “at the latest” by June 2016.
There are at least 3,000 migrants from various countries detained in Lesvos and about 800 in Samos.
Pope Francis, who used his recent Easter address to criticise the “rejection” of refugees, is to visit Lesvos on April 16.