Los Angeles: 'Citizenfour', a documentary on former US intelligence expert Edward Snowden, Sunday night won an Oscar award in the Best Documentary Feature category.
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The movie, helmed by Laura Poitras, Mathilde Bonnefoy and Dirk Wilutzky, narrates how, in 2013, computer analyst Edward Snowden leaked classified documents he had obtained from the National Security Agency, detailing the extent of government surveillance on US citizens.
Nominations in the Best Documentary Feature category also included 'Finding Vivian Maier', 'Last Days in Vietnam', 'The Salt of the Earth' and 'Virunga'.
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In the Best Documentary Short Subject category, 'Crisis Hotline: Veterans Press 1' turned out to be the winner that pipped 'Joanna', 'Our Curse', 'The Reaper (La Parka)' and 'White Earth'.