Aviation officials say a Mozambican Airlines plane was intentionally crashed by the pilot last month in Namibia.
Flight TM470 crashed en route to Angola after leaving the Mozambique capital, Maputo on November 29 carrying 27 passengers and six crew members.
Mozambican Civil Aviation Institute Chairman Joao Abreu said flight recordings showed Captain Herminio dos Santos manipulated the autopilot controls in a way that showed a "clear intention" to bring down the plane.
He said the co-pilot was locked out of the cockpit when the plane went down and that banging could be heard on the cockpit door at the time of the crash.
Abreau added the altitude selector was manually altered three times and the plane's speed was also changed.
The "black box" flight recorders were retrieved from the crash wreckage intact and analyzed by the U.S. National Transport Safety Board in Washington.
Aviation officials said the investigation was ongoing.
The dead include passengers from Mozambique, Angola, Portugal, France, Brazil and China.
Some information for this report was provided by AP and AFP.