Former SEAL Chris Kyle Allegedly Killed by Former Marine He Was Trying to Help Kyle brought suspect to shooting range for "some type of therapy," cops say.

Feb. 3, 2013 -- Former Navy SEAL Chris Kyle and his neighbor Chad Littlefield took former Marine Eddie Ray Routh to a Texas gun range to help him, but for some reason Routh allegedly turned his gun on his two mentors, killing them both, police said today.

ABC News affiliate WFAA-TV in Dallas reported that investigators said Routh, 25, was recovering from post traumatic stress disorder, but police today said they could not confirm that.

Routh, a corporal in the Marines from June 2006 to January 2010, was deployed to Iraq in 2007 and Haiti in 2010, according to the Pentagon. His current duty status is listed as reserve.

"Apparently Mr. Kyle works with people that are suffering from some issues that have been in the military and this shooter is possibly one of those people, that he had taken out to the range to mentor, to visit with, to help him, you know, that's all I can tell you," said Erath County Sheriff Tommy Bryant.

"Kind of have an idea that maybe that's why they were at the range, for some type of therapy that Mr. Kyle assists people with, and I don't know if it's called shooting therapy," Bryant said. "I don't have any idea but that's what little bit of information that we can gather so far."

Witnesses told police that Routh left the shooting scene in Kyle's pickup truck. He drove to his sister's home in Midlothian and when he allegedly told her and her husband that he had shot the two men, the couple called police.

When investigators got there, Routh fled in another vehicle, but he was captured a short time later.

Routh was charged with two counts of capital murder and was being held today at the Erath County Jail on $3 million bond.

Erath County Sheriff's spokesman Jason Upshaw said investigators have recovered the alleged murder weapon.

"Right now it appears that he used a semi-automatic handgun," Upshaw said.

Kyle, who had more than 160 confirmed kills as a sniper serving four tours in Iraq, is the author of the best-selling book "American Sniper: The Autobiography of the Most Lethal Sniper in U.S. Military History."

He helped found FITCO Cares, an organization that provides at-home fitness equipment for emotionally and physically wounded veterans, and was described by those who knew him as tireless and giving in his efforts to help vets.

"We have lost more than we can replace. Chris was a patriot, a great father, and a true supporter of this country and its ideals. This is a tragedy for all of us. I send my deepest prayers and thoughts to his wife and two children," Scott McEwen, co-author of "American Sniper," said in a statement to ABC News.

Remembering Kyle for the number of Iraqi insurgents he killed misstates his legacy, McEwen said.

"His legacy is not one of being the most lethal sniper in United States history," McEwen said. "In my opinion, his legacy is one of saving lives in a very difficult situation where Americans where going to be killed if he was not able to do his job."

Though Kyle was active in FITCO Cares, the director of the foundation said Kyle and Routh had not met through the organization.

"Chris was literally the type of guy if you were a veteran and needed help he'd help you," Travis Cox, the director of FITCO Cares, told The Associated Press. "And from my understanding that's what happened here. I don't know how he came in contact with this gentleman, but I do know that it was not through the foundation."

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Kyle, 38, served four tours in Iraq and was awarded two Silver Stars, five Bronze Stars with Valor, two Navy and Marine Corps Achievement Medals, and one Navy and Marine Corps Commendation.

From 1999 to 2009, Kyle recorded more than 150 sniper kills, the most in U.S. military history.

After leaving combat duty, Kyle became chief instructor training Naval Special Warfare Sniper and Counter-Sniper teams, and he authored the Naval Special Warfare Sniper Doctrine, the first Navy SEAL sniper manual. He left the Navy in 2009.

"American Sniper," which was published last year by William Morrow, became a New York Times best seller.

"We are devastated by the news of Chris Kyle's death," William Morrow executive editor Peter Hubbard said in a statement. "It was an incomparable honor to help share Chris's story of service and faith with the world. Chris was a hero as much on the home front as on the battlefield -- a man who dedicated his life in recent years to supporting veterans and donated the proceeds of American Sniper to the families of his fallen friends. He deserves our deepest respect. Our prayers are with his family and the entire military community. He will never be forgotten."

Kyle was also an advocate for his fellow service members suffering from PTSD, creating a foundation to help with their treatment.

In an interview on Guns.com, he discussed the difficulty troops face coming home from combat zones.

"All of a sudden you don't have no identity," he said "And you have to learn a whole new way to act."

Brandon Webb, a fellow SEAL who knew Kyle from SEAL Team Three then later when Webb was an instructor at the SEAL sniper course, called him a "larger than life Texan" and said he "will go down in history as one of the world's most accomplished military snipers, right next to Carlos Hathcock, and Lyudmila Pavlichenko."

"Chris was very adamant about supporting veterans issues," Webb said. "This was an subject close to his heart, and not many in our community realize how much of his time was spent on veterans' causes. ... Chris will be remembered as a great American Hero, and another friend lost but not forgotten."

Cox said Kyle's wife Taya and their children "lost a dedicated father and husband" and the country has lost a "lifelong patriot and an American hero."

"Chris Kyle was a hero for his courageous efforts protecting our country as a U.S. Navy SEAL during four tours of combat. Moreover, he was a hero for his efforts stateside when he helped develop the FITCO Cares Foundation. What began as a plea for help from Chris looking for in-home fitness equipment for his brothers- and sisters-in-arms struggling with Post Traumatic Stress Disorder (PTSD) became an organization that will carry that torch proudly in his honor," Cox said in a statement.

The fatal shooting comes after week filled with gun-related incidents, as the national debate heats up on what to do about gun violence.

In the past week, a teen who participated in President Obama's inaugural festivities was shot to death in Chicago, a bus driver was fatally shot and a 5-year-old was taken hostage in Alabama, and a Texas prosecutor was gunned down outside a courthouse.

The Associated Press contributed to this report.