More is being learned today about former Navy SEAL Chris Kyle and the man accused of killing the decorated Iraq War veteran.

The 38-year-old Kyle, who wrote the bestseller American Sniper about his 150-plus kills of Iraqi insurgents, and his friend Chad Littlefield, 35, were found shot to death Saturday at a gun range about 50 miles southwest of Fort Worth, Texas. As we reported Sunday, a 25-year-old former Marine named Eddie Ray Routh is in custody. Authorities say he's the only suspect in the shootings.

According to a statement posted on the website of the security training company Kyle founded, Craft International, Kyle and Littlefield appear to have been killed "by a troubled veteran whom they were trying to help."

Kyle had also created the FITCO Cares Foundation, which The Associated Press says "provides at-home fitness equipment for emotionally and physically wounded veterans." The Fort Worth Star-Telegram writes that:

"Jodi Leigh Routh, the suspect's mother, had reached out to Kyle to ask him to help her son, said Clint Burgess, a Tarrant County constable and Kyle's friend. Kyle did not know Eddie Routh, but knew his mother, Burgess said in an email from New Orleans." 'She was worried about her son and asked Chris if he could help him overcome PTSD (post-traumatic stress disorder),' Burgess said."

In Stephensville, Texas, the local Empire Tribune reports that:

"Routh ... is an unemployed former Marine who reportedly served in Iraq and Afghanistan. He may have suffered from post traumatic stress disorder and was at the gun range for some type of therapy. [Erath County Sheriff Tommy] Bryant said it appears Routh's mother may have reached out to Kyle for help with her son."

"We have an idea that that's why they were at the range, for some kind of therapy that Mr. Kyle assists people with," Bryant also told reporters, according to the Dallas Morning News. The newspaper adds that:

"Kyle was dedicated to helping veterans, especially those suffering from post-traumatic stress disorder. ... 'Our foundation, FITCO Cares, this country and most importantly, his wife Taya and their children, lost a dedicated father and husband, a lifelong patriot and an American hero,' Travis Cox, director of the non-profit, wrote in a statement released on Sunday morning. 'Chris died doing what he filled his heart with passion — serving soldiers struggling with the fight to overcome PTSD,' the statement reads."

In January 2012, Kyle spoke with member station KERA about his book and his life as a sniper. He also talked about how Americans can help veterans who served in Iraq and Afghanistan. Even simple things, he said, such as mowing a veteran's lawn or babysitting for a veteran's children "can mean the world."

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