"We held on to the boat's air chamber, many others did the same when the little boat capsized after being hit by a violent wave. But as the hours ticked by, we saw our travel companions first drift away, transported by the strong sea currents, and then vanish. We saw some as the waves engulfed them."

Just four survivors from this shipwreck were picked up in the Mediterranean by a merchant ship flying a Maltese flag and then transferred by the Italian coast guard to the Sicilian island of Lampedusa. The four, consisting of two boys and a girl, all minors and unaccompanied, and an adult man come from Guinea and the Ivory Coast.

They are all still scared and in shock as they recount the nightmare.

Unconvincing accounts?

However, the accounts of the four survivors have not been verified by Italian authorities, and, in particular, they do not always appear to be fully convincing according to several rescuers, who believe that the survivors' conditions are not compatible with the number of days at sea without water or food they say they endured.

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The flying squad at the police headquarters in Agrigento, has been taking down witness accounts from the survivors with the assistance of Italian Red Cross staff who run the first reception center on Lampedusa.

In the coming days --once the survivors have been able to overcome their shock-- the agents will listen to their accounts again. Their stories, they say appear confused and full of gaps and it is clear that the four are afraid of speaking.

According to what they have said so far, they set sail from Tunisia together with another 41 persons, among whom there were no family members or relatives. "Only friends and acquaintances. We left Sfax on Thursday," they said.

'We saw an empty boat and we managed to reach it'

Some of them said they left at 4pm and that the boat capsized approximately six hours after it set sail. But others have mentioned Thursday night as the time when the boat set sail and that the shipwreck took place during the night, perhaps in the early hours of Friday morning.

After many hours at sea, holding on to the boat's air chambers, the four survivors explained, "We saw an empty iron boat and we reached it. We were ten."

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However, as for the fate of the other six migrants who allegedly got on to the boat they found adrift and without an engine, the survivors were unable to provide an explanation. Therefore they will be questioned again in the coming hours, to try to fill in some of the gaps in their stories.

This apparent amnesia might be caused by fear of those who organized and handled the sea crossing, think investigators. "They are exhausted and I believe they are also afraid to speak", confirmed Ignazio Schintu, Deputy Secretary of the Italian Red Cross.

UN Agencies express grief about the deaths.

The UN Migration Agency IOM, UN Refugee Agency UNHCR, and the UN Children's Agency UNICEF issued a joint press release on August 9, expressing "their deep condolences for the loss of tens of human lives due to a terrible shipwreck that appears to have happened between August 3 and August 4 in the Mediterranean."

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The statement continued, "according to the witness accounts of the four survivors who were rescued by a merchant ship and safely brought to Lampedusa by the Italian Coast Guard, the number of missing people is 41, among them three children", explains the note.

"The iron boat, which set sail from Sfax (Tunisia) appears to have capsized during the course of navigation. The difficult meteorological and marine conditions in the Mediterranean over these last few days make these crossings on small iron dinghies which are inadequate for these journeys extremely dangerous. This shows the total lack of scruples of the human traffickers, who expose migrants and refugees to a high risk of death at sea. Just a few days ago a mother and her child lost their lives off the coasts of the island," continues the statement.

Over 75% of deaths in the Mediterranean in the last ten years

According to the IOM's Missing Migrants Project , there have already been 1,800 people who died and who have gone missing along the central Mediterranean route, a route that continues to be the most active and dangerous one at the global level, accounting for over 75% of victims in the whole of the Mediterranean in the last ten years," underscores IOM, UNHCR and UNICEF in the press release.

"The three United Nations organizations reiterate the need for coordinated mechanisms for search and rescue missions and they continue to ask EU member states to increase the resources and capacity to face their responsibilities effectively," concludes the press statement.