Transcript for US military investigates 2 Navy SEALs in death of Green Beret

Next to a disturbing story emerging involving members of S.E.A.L. Team six. U.S. Officials confirming the military is looking into allegations that two Navy S.E.A.L.S may have killed a green beret in June. Gloria Riviera with the latest on the investigation. Reporter: Tonight, two members from the Navy's elite S.E.A.L. Team six under a homicide investigation for the murder of a green beret in Mali, Africa. The details first reported in "The New York Times" and confirmed by ABC news, state that the Navy is examining the June incident. Rangers, green berets, S.E.A.L.S are so disciplined. So highly trained. Something like this is almost unimaginable. Reporter: The victim, staff sergeant Logan J. Melgar, found dead on assignment in Mali where special operations forces conducted training and counterterrorism missions. A U.S. Official telling ABC news the investigation is looking into asphyxiation as a possible cause of Melgar's death. The two Navy S.E.A.L.S have not been charged. S.E.A.L. Team six is among the military's most elite special operations forces. It was members of S.E.A.L. Team six that killed Osama bin laden in the 2011 raid in Pakistan. The news comes as the Pentagon investigates what led to an isis-linked ambush on October 4th in Niger that left four American soldiers dead. Sergeant Melgar's death has been described as a mystery for months. The case is now being handled by the naval criminal investigative service, who tells us they do not discuss ongoing investigations. Tom? Gloria, thank you. The Pentagon has just

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