(Recasts with charges filed against son-in-law, background)
By Tim Ghianni
NASHVILLE, Tenn., Feb 13 (Reuters) - The son-in-law of an elderly Tennessee couple killed after a package exploded at their home this week was charged Thursday with their murder, authorities said.
Richard Parker, 49, was indicted Thursday on two counts each of felony first-degree murder and premeditated first-degree murder in the deaths of retired attorney Jon Setzer, 74, and his wife Marion Setzer, 72.
"Right now, we feel like we have the single person responsible for committing this crime in custody," Mark Gwyn, director of the Tennessee Bureau of Investigation, told a news conference.
Parker was arrested Thursday afternoon at his house, which is by the home where the Setzers lived in Lebanon, Tennessee, about 40 miles east of Nashville.
Investigators from the start zeroed in on a package as the source of the explosion at 5 p.m. Monday, but had been tight-lipped about its contents or whether anyone was targeted. They released few details in announcing the charges against Parker.
Jon Setzer died in the explosion, authorities said, and Marion Setzer was flown to a Nashville hospital in critical condition, where she succumbed to her injuries Wednesday night.
The explosive package was placed at the residence, said Jeff Fulton, special agent in charge for the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives in Nashville.
An $8,000 reward had been offered for information leading to an arrest and conviction in the case and was still available Thursday, authorities said.
The Setzers attended Lebanon First United Methodist Church, Senior Pastor Mike Ripski said in a statement. Jon Setzer was a student of the Bible, beloved teacher and wise counselor, and Marion Setzer had a sweet spirit and gentle demeanor, he said.
"Their home was a 'haven of blessing and place of peace,'" Ripski said. "This horrific tragedy has left the church and all who know them in disbelief and profound grief."
Parker, who also was charged with one count of unlawful possession of a prohibited weapon, was being held on a $1 million bond, Gwyn said. (Reporting by Tim Ghianni; Editing by David Bailey, Richard Chang and Jan Paschal)