Meanwhile, Greek authorities were criticised for not acting to rescue the migrants, even though a coast guard vessel escorted the trawler for hours and watched helplessly as it sank in minutes. Greek officials argued that the migrants repeatedly refused assistance and insisted on continuing to Italy. Legal experts said that was no excuse.

The coast guard said that it had arrested nine survivors on suspicion of belonging to the smuggling ring that arranged the voyage. State-run ERT TV said the suspects were all Egyptians, adding that the ship originally left an Egyptian port for the area of Tobruk in eastern Libya, where it picked up the migrants.

Relatives of the migrants — who each paid thousands of dollars for passage on the battered vessel — gathered in the southern port city of Kalamata to look for their loved ones.

Kassem Abu Zeed said he caught the first flight from Germany to Greece after realising that his wife and brother-in-law were aboard the trawler.

“The last time we spoke was eight days ago, and (my wife) told me that she was getting ready to get on the boat,” Abu Zeed said. “She had paid $5,000″ to smugglers. “And then we all know what happened.”

Abu Zeed, a 34-year-old Syrian refugee living in Hamburg, said Esra Aoun, 21, and her 19-year-old brother, Abdullah, risked the dangerous crossing from Libya to Italy after they failed to find a legal way to join him in Germany.

The chances are low that Abu Zeed’s wife survived the sinking about 75 kilometres offshore. None of those rescued were women.

Now he hopes Abdullah may be among the men from Syria, Egypt, Pakistan and the Palestinian territories who are being temporarily housed in a Kalamata warehouse or recuperating in hospitals from hypothermia and exposure.

The chances of finding more survivors “are minimal,” retired Greek coast guard Admiral Nikos Spanos told ERT.

Erasmia Roumana, head of a United Nations refugee agency delegation, said many of the survivors have friends and relatives unaccounted for.

“They want to get in touch with their families to tell them they are OK, and they keep asking about the missing,” Roumana said.

Mohamed Abdi Marwan, who spoke by phone from Kobani, a Kurdish majority town in Syria, said five of his relatives were on the boat, including a 14-year-old. Marwan said he’s heard nothing about them since the vessel sank.

He believes his nephew Ali Sheikhi, 29, is alive, after family members spotted him in photos of survivors, but that has not been confirmed.

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“Those smugglers were supposed to only have 500 on the boat and now we hear there were 750. What is this? Are they cattle or humans? How can they do this?” Marwan said. He said each of his relatives paid $US6,000 ($8735) for the trip.

Greek authorities said the vessel appeared to be sailing normally until shortly before it sank and refused repeated rescue offers. But a network of activists said they received repeated distress calls from the vessel during the same time.

The Greek coast guard said it was notified of the boat’s presence late Tuesday morning and observed by helicopter that it was “sailing on a steady course” at 6pm.

A little later, Greek search-and-rescue officials reached someone on the boat by satellite phone, who repeatedly said that passengers needed food and water but wanted to continue to Italy.

Merchant ships delivered supplies and observed the vessel until early Wednesday morning, when the satellite phone user reported a problem with the engine. About 40 minutes later, according to the coast guard statement, the migrant vessel began to rock violently and sank.

Coast guard experts believe the boat may have run out of fuel or experienced engine trouble, with movement of passengers causing it to list and capsize.

Alarm Phone, a network of activists that provides a hotline for migrants in trouble, said the problems began much earlier in the day. The network said it was contacted by people on the vessel seeking help shortly after 3 pm. They said they “cannot survive the night.”

Around 6:20 pm, Alarm Phone wrote, migrants reported the vessel was not moving and that the captain had left on a small boat. The two accounts could not immediately be reconciled.

Experts said maritime law would have required Greek authorities to attempt a rescue if the boat was unsafe, regardless of whether passengers requested it.

Search and rescue “is not a two-way contract. You don’t need consent,” retired Italian coast guard Adm. Vittorio Alessandro said.

An aerial photograph of the vessel before it sank released by Greek authorities showed people crammed on the deck. Most were not wearing life jackets.

Overcrowding, a lack of life vests, or the absence of a captain would have all been reasons to intervene, Alessandro said.

Professor Erik Røsæg from the University of Oslo’s Institute of Private Law said Greek authorities definitely “had a duty to start rescue procedures” given the condition of the trawler.

He said a captain’s refusal of assistance can be overruled if deemed unreasonable. “It appears that the refusal in this case was highly unreasonable,” Røsæg said.

Greece’s caretaker minister for civil protection, Evangelos Tournas, defended the coast guard’s conduct, saying it couldn’t intervene with an unwilling vessel in international waters.

“Consider also that an intervention by the coast guard could have placed an overloaded vessel in danger, which could capsize as a result,” he said.

The trawler sank near the deepest part of the Mediterranean, where depths of up to 5,200 meters c could hamper any effort to locate a sunken vessel.

Human rights groups say a European Union crackdown on smuggling has forced people to take longer, more dangerous routes to reach safe countries.

Eftychia Georgiadi, an official in Greece with the International Rescue Committee charity, said the EU’s failure to offer more safe pathways to migration “effectively slams the door on people seeking protection.”

“Nobody embarks on these treacherous journeys unless they feel they have no other option,” she said.

AP

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