WASHINGTON — The military is investigating whether two special forces Marines played a role in the choking death of a Green Beret in Mali last year and the possible cover up of how it occurred, according to five U.S. defense officials.

Two Navy SEALs from the famed SEAL Team 6 are already under investigation for their involvement in the strangling death of Staff Sgt. Logan Melgar during the predawn hours of June 4, 2017. Melgar, 34, died in embassy housing he shared with other service members in Bamako, capital of the West African nation.

A September 2017 Army Criminal Investigative Division report about the incident quotes Navy SEAL Tony DeDolph saying he and Army Staff Sgt. Logan Melgar were wrestling at 4 a.m. when a fellow SEAL Adamcranston Matthew came in and joined in the horseplay. According to the SEALS, the men fell down together and when they stood up Melgar wasn’t breathing.

The SEALs say they attempted CPR and tried to open an airway, but Melgar died of asphyxiation.

The same report, however, says a witness told investigators that DeDolph and Matthews were among a group of people angry at Melgar, and had made comments about getting back at him.

According to that witness, "DeDolph admitted … that he ‘choked [Melgar] out.’ " and had used duct tape on him.

A military medical examiner ruled that Melgar’s death was "homicide by asphyxiation."

Now forensic evidence uncovered during a Navy investigation indicates two Marines may have been present at some point during the night, say five U.S. defense officials.

Adam Stump, spokesperson for the Naval Criminal Investigative Service, which has been probing the incident, declined to comment on the two Marines.

"We don’t talk about open investigations," Stump said.

A spokesperson for U.S. Marine Special Operations Command also declined to comment on the two Marines.

"It is our policy not to comment on ongoing investigations," Maj. Nick Mannweiler said.

According to the New York Times, Melgar was in Mali to provide intelligence to the U.S. ambassador about Islamic militants while the SEALs were in Mali on a clandestine mission. SEAL Team 6 is best known for the 2011 operation that killed al Qaeda leader Osama bin Laden.