Chris Kyle Death: Photos seized from suspect Eddie Routh's phone may show ex-Navy SEAL before death

(CBS/AP) LANCASTER, Texas - Authorities have seized a cellphone from the home of Iraq War veteran Eddie Routh, who is accused of killing former Navy SEAL sniper Chris Kyle and his friend. The phone may contain pictures of Routh with the victims before their deaths at a Texas shooting range, according to police documents released Thursday.

Pictures: Ex-Navy SEAL fatally shot on Texas gun range

The phone, a box of 9 mm ammunition, drug paraphernalia and a blue-jean jacket were seized from the 25-year-old Routh's home after he was arrested near his house in Lancaster, Texas, according to a police search warrant affidavit, inventory sheet and other documents.

Routh allegedly confessed to shooting Kyle, author of the best-selling book "American Sniper," and Chad Littlefield on Saturday afternoon at Rough Creek Lodge in Glen Rose. Police believe he used the phone after the shooting to call his sister before driving Kyle's truck to her house. Routh told his sister and brother-in-law that the men "were out shooting target practice and he couldn't trust them so he killed them before they could kill him," according to the affidavit.

A public memorial service for the 38-year-old Kyle, reputed to be the deadliest sniper in American military history, is scheduled for Monday at Cowboys Stadium near Dallas. A funeral service for the 35-year-old Littlefield was set for Friday in Midlothian.

Routh is charged with one count of capital murder and two counts of murder. He remains jailed in Erath County on a $3 million bond.

Routh's attorney, R. Shay Isham, has said he will ask for a court-appointed psychiatrist to determine if Routh is competent to stand trial. His other court-appointed attorney, J. Warren St. John, said Routh was released from the Dallas Veterans Affairs hospital against his family's wishes just two days before the shootings.

In September, Routh was transported to a psychiatric hospital after he threatened to kill himself and his family, and he later told officers that he suffered from post-traumatic stress disorder, Lancaster police records show.

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