By Joe McDonald

MOUNT POCONO, PA. (Reuters) - The parents of a Pennsylvania state trooper slain by a sniper outside his barracks last fall declared their forgiveness on Sunday for the defendant, a survivalist awaiting trial on murder charges that carry a possible death sentence.

Bryon and Darla Dickson spoke about the death of their son, police Corporal Bryon Dickson, and the healing power of forgiveness during three "Blue Sunday" services honoring law enforcement at the Community Church in Mount Pocono, about 110 miles north of Philadelphia.

Following the services, Dickson's father told Reuters in the church lobby that he and his wife had spoken with the congregation about their's death, "how we dealt with it," and why they embraced forgiveness for his killer.

“The only alternative is bitterness," the church pastor, David Crosby Jr., added. "Forgiveness is the difference between becoming bitter and getting better.” Dickson nodded in agreement.

Asked about Frein, Dickson said, “For some reason, he didn’t like the police. We don’t know why.”

Corporal Dickson, 38, and fellow trooper Alex Douglass, 31, were gunned down on Sept. 12, 2014, during a late-night shift change outside the Blooming Grove barracks in the thick woods of eastern Pennsylvania. Douglass was seriously wounded.

After a seven-week manhunt by hundreds of state and federal law enforcement that cost an estimated $11.7 million, the suspect, Eric Frein, was apprehended near an old airstrip at Birchwood, an abandoned resort in the Poconos. A survivalist and Serbian war re-enactor, Frein was unemployed and had been living with his parents in the area before the killing, according to authorities.

He was on the FBI’s list of most wanted fugitives while at large, and has been held without bail while awaiting trial on homicide charges. No trial date has been set.

Pike County District Attorney Ray Tonkin has said he will seek the death penalty if Frein is convicted of first-degree murder in Dickson's death. Frein, who turned 32 on Sunday, also is charged with shooting Douglass.

(Editing by Steve Gorman and Jeffrey Benkoe)