(CN) — Navy officials this week said they will investigate discrepancies in the number of medals "American Sniper" Navy SEAL Chris Kyle was awarded, after documents surfaced that contradict claims he made in his best-selling autobiography.
Kyle, who was murdered by an ex-Marine he was trying to help in 2013, rose to fame after the success of his book, "American Sniper," and a hit movie of the same name in 2015.
"All told," Kyle wrote in his book, "I would end my career as a SEAL with two Silver Stars and five Bronze [Stars], all for valor."
But Navy documents obtained through the Freedom of Information Act show Kyle was awarded just one Silver Star and three Bronze Stars, the online news site The Intercept reported on Wednesday.
Kyle had been warned at least once that his medal count was wrong before he published his autobiography, a Navy official told The Intercept.
Navy spokeswoman Lt. Jacqueline Pau said Wednesday that officials are trying to figure out why Kyle's files showed a different count.
The Silver Star is the third-highest military combat decoration troops can receive for bravery. The Bronze Star is awarded for heroic achievement or meritorious service in a combat zone.
Kyle ended his 11-year Navy career in 2009 and has been called the most lethal sniper in U.S. history. His widow, Taya Kyle, testified at the 2015 trial of his murderer that her husband had "between 155 to 160 confirmed kills."
A Texas jury on Feb. 24, 2015, convicted Eddie Ray Routh of murdering Kyle and his friend Chad Littlefield. They had befriended the troubled veteran at the request of Routh's mother. Routh, then 25, killed them with a total of 13 bullets at a Dallas shooting range.
Routh was automatically sentenced to life in prison without parole for the 2013 slayings and has appealed to Texas 11th Court of Appeals.
Routh's attorney asked for a new trial in December 2105, but state prosecutors argued in a March brief that overwhelming evidence is sufficient to support the jury's rejection of Routh's insanity defense.
Both parties have requested oral arguments before the appellate court.
Kyle came under fire in the past for claims made in his book.
A Minneapolis jury in 2014 awarded $1.85 million in damages to Jesse Ventura in his defamation case against Kyle, who said he punched out the former Minnesota governor in 2006 for criticizing the SEAL's role in the Iraq War.
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