Austrian police said the body of Shokri Ghanem was found last weekend. There were no signs of foul play, Roman Hahslinger, a spokesman for the Vienna police, told Bloomberg News, but it is unknown how Ghanem died.
It wasn't clear where Ghanem was working at the time though he had served as an official at the Organization of Petroleum Exporting Countries during his tenure in the government of Moammar Gadhafi. OPEC has headquarters in Vienna.
Ghanem defected from the Gadhafi government during the civil war last March.
Ghanem, before his defection, said non-Western countries could be favored in his country unless companies like French energy giant Total and Germany's Wintershall return to work in Libya.
Ghanem served in Libya as the prime minister from 2003-06 and as oil minister until his defection. The U.S. Department of the Treasury's Office of Foreign Assets Control announced that it had removed sanctions against him in June.
Tripoli last week hosted a major international oil and natural gas conference. Libya's oil sector has rebounded since the end of hostilities, though allegations have since surfaced that much of the sector was mired in corruption.
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