SAN DIEGO (Reuters) - Military prosecutors said on Friday they will not drop premeditated murder charges against a U.S. Navy SEAL charged with stabbing to death a teenaged Islamic State militant in Iraq in 2017, despite testimony from another SEAL who claimed to have killed the prisoner.

FILE PHOTO: U.S. Navy SEAL Special Operations Chief Edward Gallagher arrives at court with his wife Andrea and brother Sean (C) for the start of his court-martial trial at Naval Base San Diego in San Diego, California, U.S., June 18, 2019. REUTERS/Mike Blake/File Photo

Navy SEAL medic Corey Scott told the court on Thursday that he held his thumb over the victim’s breathing tube until he died, saying he did so to save the young militant from being tortured by Iraqi forces.

Scott said the young man’s original injuries - a leg wound and collapsed lung - were not life threatening but that he was breathing through the tube when Navy SEAL Special Operations Chief Edward Gallagher stabbed him in the neck.

“The government will not be dropping premeditated murder charges against Chief Petty Officer Gallagher, despite petty officer Scott’s testimony,” the Navy said in a statement. “The credibility of a witness is for the jury to decide.”

Scott, like other SEALs in Gallagher’s unit, has been granted immunity from prosecution in exchange for his testimony. The prosecution accused Scott in court on Thursday of lying to protect Gallagher, and said his testimony contradicted his previous statements to them and the testimony of other SEALs.

The Islamic State fighter had been captured by Iraqi forces following house-to-house fighting in Mosul and dumped on the ground at a base outside the Iraqi city, the prosecution said in its opening statement on Monday.

Prosecutors say Gallagher, 39, who began his 18-year career as a medic, briefly treated the young Islamic State fighter, then pulled out his knife and stabbed him in the neck.

MURDER OR MUTINY?

The seven-sailor jury at the court martial must decide whether the fighter’s death was murder as alleged by the prosecution or a mutiny by sailors under Gallagher’s command in Iraq, as the defense contends.

Gallagher is also charged with attempted murder in the wounding of two civilians, a schoolgirl and an elderly man, shot from a sniper’s perch in Iraq. He could face life in prison if convicted.

On Friday Navy SEAL Dalton Tolbert, who served under Gallagher, testified that he did not see the shot in the case of the elderly man but did see blood appear on the man’s back before he fell.

“I saw Eddie Gallagher shoot someone who didn’t deserve to die,” Tolbert said.

Another SEAL, Joshua Vriens, testified Gallagher admitted killing the teen ISIS fighter.

“He said, I stabbed him in the side and then I looked him in the eyes and stabbed him in the neck,” Vriens testified.

Defense attorney Tim Parlatore said on Thursday the surprising admission from Scott that he had asphyxiated the wounded fighter showed the prosecution never asked about the cause of death and the Navy Criminal Investigation service had gone into the case with minds made up.

Gallagher’s wife, Andrea, told reporters after Thursday’s court session ended: “We’ve been patiently waiting for the truth to come out. It’s been lies, half-truths and cover-ups till now.”

The court martial has drawn national attention and President Donald Trump said last month that he was considering pardons for a number of military service members accused of war crimes; Gallagher’s case was believed to be one of those under review.