CATANIA, Sicily (AP) — The United Nations refugee agency said Tuesday that it believes more than 800 people drowned when a boat packed with migrants trying to reach Europe sank on Saturday, making it the worst such incident ever in the Mediterranean.
New details of the tragedy were emerging as the U.N. High Commissioner Refugees and other aid agencies interviewed the handful of survivors who arrived overnight in Catania, Sicily.
Survivors put the number of passengers on board the three-deck fishing trawler at 850, according to UNHCRspokesman Adrian Edwards in Geneva. Only 24 bodies were recovered, in addition to the 28 survivors.
"From available information and the various accounts we've had UNHCR now believes the number of fatalities to have been over 800 making this the deadliest incident in the Mediterranean that we recorded," Edwards told reporters in Geneva.
Among the arrivals overnight were two suspected smugglers, who were immediately detained for investigation of aiding and abetting illegal immigration, reckless homicide and causing a shipwreck.
The newly arrived survivors told UNHCR that the wreck was caused when one of the smugglers crashed the boat against the Portuguese-flagged King Jacob container ship that responded to a distress call, according toUNHCR spokesman Carlotta Sami.
"The survivors said that the person who was steering the boat, their smuggler, was navigating badly, and he did a bad move that made it crash against the bigger ship," Sami said by telephone from Sicily. The ship pitched in the water before finally tipping over, and sinking.
Several hundred people were locked on the lower level, hundreds more were inside a second level and hundreds more were on deck, according to prosecutors.
Sami said the Portuguese ship had previous experience with migrant rescues and praised its efforts, and that of other merchant ships.
While the search continued for survivors and bodies, the depth of the sea where the tragedy took place off the Libyan coast made it unlikely more would be recovered, as is typically the case.
The weekend deaths have jolted the European Union into taking action, with Italy demanding that it not be left alone to shoulder the burden of rescues and that the EU focus on preventing the boats from leaving Libya in the first place.
Combatting the smugglers by arresting the ringleaders and destroying their boats is emerging as a key part of Europe's 10-point proposal for an emergency summit in Brussels on Thursday. Italy has arrested more than 1,000 smugglers, most of them the navigators and not the masterminds, but says it needs help.
Catania prosecutors said the capsizing was due to two factors: The smuggler captain, Mohammed Ali Malek, 27, by mistake rammed his boat into the Portuguese-flagged cargo ship that had come to its rescue. In addition, the migrants themselves then moved around on the overcrowded boat, which was already unbalanced from the collision, making it capsize.
The survivors were brought Tuesday to a migrant holding center in Catania and were "very tired, very shocked, silent," according to Flavio Di Giacomo of the International Organization for Migration.
Sami said all the survivors were men, several of them adolescents. "They are very confused, fragile and scared," she said.
The coast guard, meanwhile, reported that it saved some 638 migrants in six different rescue operations on Monday alone. On Tuesday, a further 446 people were rescued from a leaking migrant ship about 80 miles (130 kilometers) south of the Calabrian coast.
The smugglers use a variety of boats for their crossings, from rubber Zodiac-type boats to wooden fishing vessels and even old cargo ships. They are always overcrowded to maximize the revenue of the smugglers, who charge between 1,000 and 1,500 euros (dollars) for the crossing from Libya, where most trafficking operations originate.
The EU plan calls for closer law-enforcement coordination to trace smugglers' revenue sources, which prosecutors have said often evade traditional bank transfers in favor of informal Arab hawala networks, in which migrants' relatives in Europe pay local brokers for each leg of the journey.
Italy had launched a robust and expensive search-and-rescue mission in 2013 after some 366 migrants drowned off the island of Lampedusa. The politically unpopular Mare Nostrum operation ended last year, and the EU's Frontex border patrol mission took charge. But its limited mandate and resources have prevented it from being effective in saving lives.
The International Organization for Migration says the 2015 rate of migrant deaths in the Mediterranean is much bigger than last year, when a total of 3,279 migrants died.
The number of deaths this year "could well top 30,000," said Joel Millman, spokesman for the Geneva-based organization. "We just want to make sure people understand how much more ... rapid these deaths have been coming this year than last year."
The number of migrant deaths in the Mediterranean already this year is 1,776, according to the U.N. refugee agency, which also estimates that 219,000 people made the crossing last year.
Barry reported from Milan. Frank Jordans in Berlin and Nicole Winfield in Rome contributed to this report.
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