To a story rocking the rural town of Lebanon, Tennessee. A mail bomb going off in the hands of a homeowner leaving a devastating scene behind. ABC's Pierre Thomas has the latest and joins us now from... See More
To a story rocking the rural town of Lebanon, Tennessee. A mail bomb going off in the hands of a homeowner leaving a devastating scene behind. ABC's Pierre Thomas has the latest and joins us now from Washington. Good morning, Pierre. Reporter: Good morning, robin. Today a murder mystery unfolding in small town Tennessee. Authorities fear this may be only the beginning. The shattered windows of this lovely home hint of the devastation inside from a blast that could be heard from miles away. I heard a big boom. Thought someone might have actually backed into the building next to my office. Reporter: Authorities say 74-year-old retired lawyer don Se tempt zer after a powerful package bomb exploded in his home and his wife was critically wounded in the attack and this morning is clinging to her life at the Vanderbilt university medical center. Overnight police continue to sift through the rubble looking for evidence and trying to find part of the bomb and the package it came in. Police have no motive in the attack and are offering an $8,000 reward for any leads. We completely rely on the public assistance so that we can follow up on any lead. Reporter: The bombing happened about 31 miles outside of Nashville in tiny Lebanon, Tennessee. A place where this kind of savage attack just doesn't happen. They're just the perfect neighbor and we felt like this was a place that nothing would ever happen. Reporter: This morning police are warning rest dents in the area to be careful of unexpected packages. Translation, no one knows if more package bombs are coming. Robin? So frightening, Pierre, thank you.
This transcript has been automatically generated and may not be 100% accurate.