Van der Sloot, 24, a Dutch national long considered a key figure in the unsolved 2005 disappearance of Alabama teenager Natalee Holloway in Aruba, was arrested in 2010 in the death of Flores but was not charged until earlier this month.
The video, aired on the CNN affiliate America TV, shows van der Sloot explaining to an interrogator how he hit and strangled Flores in his Lima hotel room after he saw her pulling up information about him on his computer, CNN reported Tuesday.
Attorney Luis Jiminez Navarro has said his client was willing to confess to a "simple homicide" charge, the report said.
Van der Sloot was arrested twice but never charged in Holloway's 2005 disappearance and presumed death in Aruba while on a senior trip.
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