Washington (CNN) President Donald Trump on Monday granted a pardon to a former first lieutenant in the US Army who was sentenced to prison in 2009 for killing an Iraqi detainee, according to the White House.

White House press secretary Sarah Sanders announced that Michael Behenna, of Oklahoma, would receive a full pardon. In a statement, Sanders said Behenna had been sentenced to 25 years in prison for unpremeditated murder in a combat zone by a military court, but there were issues involving his case.

"After judgment, however, the U.S. Army's highest appellate court noted concern about how the trial court had handled Mr. Behenna's claim of self-defense," Sanders said in the statement.

"Additionally, the Army Clemency and Parole Board reduced his sentence to 15 years and paroled him as soon as he was eligible in 2014 -- just 5 years into his sentence," she added.

Behenna deployed to Iraq in 2007, according to The Washington Post . The following year, two soldiers and friends of Behenna were killed in a roadside explosion and he was on the scene, the newspaper reports.

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