Sikorski's death controversy

Władysław Sikorski's death controversy revolves around the death of the commander-in-chief of the Polish Army and Prime Minister of the Polish government in exile, General Władysław Sikorski, in the 1943 B-24 crash in Gibraltar. Sikorski's Liberator II crashed off Gibraltar almost immediately after take off, with the plane's pilot being the only survivor. The catastrophe, while officially classified as an accident, has led to several conspiracy theories that persist to this day, and often propose that the crash was an assassination, which has variously been blamed on the Soviets, British, Nazis or even a dissenting Polish faction. The incident is still described by some historians as mysterious, and since 2008 it has been under an investigation by the Polish Institute of National Remembrance, ongoing as of July 2013.

In late May 1943, Sikorski went to inspect Polish forces stationed in the Middle East. He was inspecting the forces and raising morale of the Polish troops there. He was also occupied with political matters; around that time, a conflict was growing between him and general Władysław Anders. The main reason for this was that Sikorski was still open to some normalization of Polish-Soviet relations, to which Anders vehemently objected.

On 4 July 1943, while returning from the Middle East, Sikorski perished, together with his daughter, his Chief of Staff, Tadeusz Klimecki, and seven others, when his aircraft, a Consolidated Liberator II, serial number AL523, crashed into the sea 16 seconds after takeoff from Gibraltar Airport at 23:07 hours.

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Wikipedia