NEW YORK // The US military's most deadly Iraq sniper was shot to death at a firing-range, apparently while he was helping a fellow veteran who suffered from post-traumatic stress disorder.
Former Navy SEAL sniper Chris Kyle, 38, and his friend Chad Littlefield, 35, died at a posh shooting range in Texas on Saturday after being shot multiple times by Eddie Ray Routh, 25, an apparently unstable Marine reservist, law enforcement authorities said.
The alleged killer has not given a motive. "I don't know that we'll ever know," said Captain Jason Upshaw of the Erath County Sheriff's Office. "He's the only one that knows that."
After serving four tours of duty in Iraq during the US occupation's bloodiest years, Kyle retired in 2009, penning the best-selling book American Sniper and founding a non-profit organisation to help fellow veterans overcome their mental battle scars and struggles with re-entering civilian life.
"Chris struggled with some things," Travis Cox, the director of Kyle's non-profit Fitco Cares, told the Associated Press. "And he found a healthy outlet and was proactive in his approach to deal with those issues and wanted to help spread his healing, what worked for him, to others. And that's what he died doing."
Erath County Sheriff Tommy Bryant said: "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."
Mr Routh, a decorated Iraq war veteran, was captured Saturday evening near his home in a Dallas suburb after a car chase. Police said they recovered a semi-automatic weapon they believe was used in the killing from his house.
He charged with two counts of capital murder.
Mr Routh allegedly succeeded where no Iraqi insurgent was able to, even after they put a $20,000 (Dh73,464) bounty on Kyle's head and dubbed him "Shaitan Al Ramadi", which translates to "The Devil of Ramadi", according to US military officials.
Kyle, the deadliest sniper in US military history, never divulged exactly how many enemy fighters he killed. Military officials certified more than 150 of his kills, but the number could reportedly be over 250.
Kyle survived two shootings and six improvised explosive device attacks in Iraq and wrote unrepentantly about his experiences there in his book.
After shooting an Iraqi woman with a child, who reached for a grenade as US troops approached her, Kyle wrote, "It was my duty … and I don't regret it. My shots saved several Americans, whose lives were clearly worth more than that woman's twisted soul," according to The New York Times.
"It just comes as a shock and it's staggering to think that after all Chris has been through, that this is how he meets his end, because there are so many ways he could have been killed," Scott McEwen, who wrote the book with Kyle, told Reuters.
The murders are the latest shooting incidents that have come amid an intense debate around gun control and mental health sparked by the school shooting at Sandy Hook Elementary School nearly two months ago.
Kyle, who had become a minor celebrity with the publication of his book, was interviewed by the website guns.com after the school shooting about calls for stricter gun laws and said he did not support them and favoured arming teachers.
His second book, American Gun: A History of the US in Ten Firearms, is to be published in May.
Kyle's death will likely bring to the gun debate the issue of PTSD among US service members. More than two million have served in Iraq and Afghanistan.
"The symptoms can range from mildly disturbing to wholly incapacitating," Jeffrey Lieberman, chair of psychiatry at Columbia University Medical Center in New York, told ABC News. "And we're still limited in our understanding of why it occurs, what it consists of and the best approaches to treatment."