A damning new report into the death of dozens of African migrants who were left drifting in the Mediterranean last year has concluded that Nato contributed to the 63 fatalities, and raises for the first time the possibility of British military forces being connected with the tragedy.
The exhaustive, 90-page study by experts at Goldsmiths, University of London makes use of cutting-edge "forensic oceanography" technology to determine the exact movements of the doomed migrant vessel, which was left drifting without power for two weeks in one of the busiest shipping lanes in the world, despite European and Nato officials having been aware of the boat's plight and location. Almost everyone on board, including two small babies, eventually died of thirst and starvation.
The report reveals that the survivors' description of a military helicopter that twice hovered over and communicated with their boat, only to then fly and off and abandon them without attempting a rescue, corresponds almost exactly to the British army's Westland Lynx helicopter. Units of Lynxes are known to have been operating in the Mediterranean at the time of the Libyan conflict.
The Guardian is waiting for a response from the British Ministry of Defence on the report's contents
The report also quotes survivor testimony suggesting that a naval vessel that came into direct contact with the migrants, only to also ignore their cries for help, could have been French.
The latest revelations will increase the pressure on Nato to release classified imagery and data that could help identify the units responsible for failing to mount a rescue operation. The question of which units those were has gained added significance since European human rights lawyers said recently criminal action would be launched against those deemed culpable of the deaths.
Last month, an investigation into the incident by the Council of Europe, the continent's human rights watchdog, found that a catalogue of institutional and legal failures had resulted in the unnecessary and avoidable deaths of the migrants. It called on Nato and its member states to launch their own inquiries into why so many military units, including a Spanish frigate under Nato command that was sailing in the immediate vicinity of the boat, failed to respond to the migrants' desperate pleas for help. A row subsequently erupted between Nato and Spain, after the Spanish ministry of defence publicly contradicted Nato's official version of events.
The latest report draws together scientific expertise from London, New York and Berlin, and utilises advanced remote-sensing and drift-modelling technology. It outlines the scale and sophistication of Nato's maritime surveillance operation in the Mediterranean at the time of the Libyan conflict, and the ease with which a rescue of the stricken boat could have been undertaken.
It echoes the Council of Europe in condemning Nato, and claims to demonstrate "a high degree of involvement on the part of participating states/Nato command and assets that contributed to the death of 63 passengers on board the 'left-to-die boat' and to grave psychological and physiological consequences for all 72 passengers."
Nato initially denied any knowledge of the migrant boat, only later to admit that the Italian coastguard had informed it of the boat's location. The military alliance insists this information was passed on to the units under its control, but the Spanish have challenged Nato to prove the claim; Nato has since refused to answer questions on the matter.
The new report seeks to establish exactly which military helicopter and naval vessel made contact with the migrants only to leave them adrift at sea, despite the passengers holding aloft dead babies and empty fuel tanks to indicate their predicament.
Although the lack of co-operation from military forces has so far made a definitive identification impossible, the report uses the migrant survivors' own description of the helicopter to rule out nearly all of the models that may have been based in the Mediterranean at that time, with the exception of the British Lynx.
One of the survivors was shown a series of photos depicting different types of helicopters; on seeing the Lynx he immediately told researchers that the helicopter that made contact with the migrant boat was "exactly like this".
Britain was the only country apart from the US that refused to co-operate with the original Council of Europe investigation into the migrant boat tragedy.
On the identity of the naval vessel, the report quotes one survivor alleging that the frigate was flying a French flag and claiming that the migrant boat captain, who later died on board the dinghy, described "everything" about the ship as being French. But the report's authors point out that several frigates of various national origin operating in the Mediterranean at that time could correspond to the survivors' description of the vessel.
The report concludes that vital classified information must now be released by national militaries and Nato in an effort to ensure accountability for those who died. "Participating states/Nato forces had the information and the ability to assist the migrants but failed to do so in a way that would have prevented the deaths of 63 people," the authors state. "Only through further inquiry and disclosure by all parties involved will they receive the definite answers they deserve.