The son-in-law of the Tennessee couple who was killed by a mail bomb has been charged with their murder, investigators announced today.

Police arrested 49-year-old Richard Parker on two counts of felony first-degree murder and two counts of felony premeditated murder in connection with the deaths of John Setzer, 74, and Marion Setzer, 72.

The package bomb was delivered to the mailbox of the Setzer home in Lebanon, about 30 miles east of Nashville. Mr. Setzer carried the package Monday from the mailbox to his home; a distance of about 200 yards. Once inside, the bomb exploded and instantly killed Mr. Setzer and mortally injured Mrs. Setzer. She later died Wednesday night at Vanderbilt Hospital.

Police have not released a motive for the bombing, but have found a note they believe may have been attached to the bomb. The contents of the note are being kept private.

Parker’s bail is set at $1 million. Right now he is the sole suspect. He was convicted of arson in 1994 and served four years on probation.

Officials are investigating just how the bomb was delivered; whether it was sent through the United States Postal Services or by a private carrier. It was initially believed that the package was sent through the USPS, but now the issue is being investigated further.

Mr. Setzer was a lawyer who worked on bankruptcy and general will cases, along with living trusts, before he retired due to health issues. Those close to the couple don’t understand why they were targeted.

“Nothing had happened in my recent times to make me anticipate anything of this kind happening,” said Setzer’s former law partner George Cate, Jr.

“It doesn’t make sense at all,” said family friend Ken Caldwell. “When I’ve heard it said that it was targeted, I thought, well, they must have targeted the wrong person.”

After the bombing, investigators searched the neighborhood and other mailboxes for similar packages. Police have offered a reward for leads pertaining to the case.

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