STEPHENVILLE, Texas (AP) — A former Marine charged in the shooting deaths of "American Sniper" author Chris Kyle and another man exhibited symptoms of psychosis in the weeks leading up to the slayings, a forensic psychiatrist testified Thursday.

Dr. Mitchell H. Dunn, testifying as a defense witness, said Eddie Ray Routh was in a psychotic state when Kyle, a famed Navy SEAL sniper, and his friend, Chad Littlefield, were killed on Feb. 2, 2013, The Dallas Morning News ( ) reported. Dunn said Routh suffers from schizophrenia.

The trial has drawn intense interest, partly because of an Oscar-nominated film based on Kyle's memoir.

Routh, 27, has pleaded not guilty to capital murder, and his attorneys are mounting an insanity defense. Prosecutors are not seeking the death penalty, so he faces life without parole in prison if convicted.

About a week before the slayings, Routh had been released from the hospital after having a psychotic episode. Dunn said that after Routh returned to work, he thought two of his co-workers were cannibals who were going to harm him.

Routh's friends and family have testified that his behavior in the weeks before the killings was increasingly erratic. They said he acted as if he believed that someone was going to hurt him and that the government was listening to him.

Dunn, who spent more than six hours interviewing Routh in April 2014 to determine his state of mind when he shot the men, testified that Routh described seeing neighbors and friends as turning into pig-human hybrids.

The doctor said Routh was displaying signs of schizophrenia as early as 2011, when he was first taken to the mental hospital. Routh left the Marines in 2010.

Dunn also looked at crime scene reports, police interviews and Routh's medical records.


Information from: The Dallas Morning News,

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