By Adam Easton
BBC News, Warsaw
The general was the leader of Poland's government-in-exile
Prosecutors in Poland have announced they will exhume the body of the country's World War II prime minister.
Gen Wladyslaw Sikorski will be exhumed as part of a inquiry to decide whether his death in a plane crash in Gibraltar in 1943 was an accident or murder.
A British investigation ruled that it was an accident, but some historians in Poland believe Gen Sikorski died as a result of foul play.
Poland's president and prime minister are backing the current inquiry.
The general's body will be exhumed in two weeks from the crypt of Krakow Cathedral, where it lies next to Polish monarchs and national heroes.
Prosecutors say it may provide clues to help them determine whether Gen Sikorski was assassinated.
During the war the general was prime minister of the Polish government-in-exile in London.
In July 1943, the Liberator aircraft he was travelling on together with two British MPs, crashed into the sea just seconds after it took off from Gibraltar.
A British investigation at the time found the plane's controls had jammed. But a separate Polish investigation did not rule out he may been murdered.
The general's death has produced several colourful conspiracy theories despite a lack of evidence.
At the time Gen Sikorski had demanded an investigation into allegations that Poland's then ally, the former Soviet Union, had massacred more than 20,000 Polish officers in the forests of Katyn three years earlier.
Some even believe British Prime Minister Winston Churchill may have ordered his death to preserve good relations with Stalin.
However, prosecutors have said they are investigating a "communist crime", suggesting that the suspicion falls on the former Soviet Union.