Athens (AFP) - Human Rights Watch (HRW) on Tuesday called on Greece to reverse its "draconian policy" towards over 450 migrants detained on a navy ship docked in Mytilene port in Lesbos.
The men, women and children were among those picked up by the Greek Coast Guard since March 1, when Turkey decided to open its borders and let make the crossing.
Since Turkey's February 28 decision, more than 1,700 people have arrived on the Greek islands in the Aegean off the Turkish coast.
Many of those who reached Lesbos, which is already struggling to cope with the numbers of migrants there, were transferred last Wednesday to the ship.
HRW, quoting a Syrian asylum seeker on board, said many of the 451 detained were women and children and criticised the conditions on board.
On March 1, Greece announced it would not accept asylum requests from the new arrivals the day after Ankara opened its borders, a decision condemned by the UN refugee organisation UNHCR.
"Greece’s decision to detain more than 450 people on a naval vessel and refuse to allow them to lodge asylum claims flagrantly violates international and European law," Human Rights Watch said in a statement.
"The action may amount to an arbitrary deprivation of liberty."
Bill Frelick, HRW's director of migrant and refugee rights, added: "Greece should immediately reverse this draconian policy, properly receive these people in safe and decent conditions, and allow them to lodge asylum claims".
- Conditions on board -
Human Rights Watch said that the Greek authorities had denied them access to the dock area where the detainees were kept during the day -- or to the vessel where they spend the night.
The Syrian, who contacted HRW by telephone, said most of the detainees were Afghans, but that 118 are Arabs, including Syrians, Iraqis and Palestinians. Somalis, Congolese, and others from Africa were also on board.
"The children are not receiving sufficient food and clothing," he told HRW.
"We had only three toilets for 451 people until today, when they brought five portable toilets. There is no shower, no soap."
Pregnant women were among those detained, but it was not clear if they were getting proper medical care, he added.
He also said he had been denied direct access to a lawyer.
In Lesbos, more than 19,000 refugees live in miserable conditions in the Moria camp, which was built to hold fewer than 3,000 people.
Tension has escalated on the island with the upsurge in arrivals last week.
The Greek government's decision last month to build new closed camps on the islands, provoked an angry backlash from residents.