by Danielle Wallace, David Spunt
It appears to be a "lone wolf" situation, but the motive remains under investigation.
Authorities believe Warner owned the RV that exploded in downtown Nashville early Friday, sources said. He also is believed to be deceased from the blast.
Human tissue was found amongst the debris left behind by the explosion, and investigators will be conducting DNA testing.
Metro Nashville Police Department Spokesman Don Aaron confirmed Warner's identity to the Associated Press on Sunday. He did not provide any more details. However, Warner had experience with electronics and alarms, according to public records.
Warner was believed to have lived at the home in Antioch, Tenn., searched for several hours Saturday by the FBI and several other law enforcement agencies. The home address on Google Earth shows the same RV parked in different places on the property dating back several years.
It appears to be a "lone wolf" situation, but the motive remains under investigation. Authorities do not believe the city of Nashville is in danger.
Separately, a law enforcement official told The Associated Press that federal investigators have started examining Warner's digital footprint and financial history. They are also examining a recent deed transfer of a home in suburban Nashville.
Police said the RV sounded warnings to evacuate and a 15-minute countdown to clear the area. The voice of the woman on the recording is believed to be a robotic, computerized voice, the sources said.
The RV also blasted a song before it detonated, which was identified by law enforcement as "Downtown" by Petula Clark.
Investigators continued to piece together how this individual could have assembled a bomb and over what time frame.
"It’s just going to take us some time," Douglas Korneski, the special agent in charge of the FBI’s Memphis field office, said at a Saturday afternoon news conference. "Our investigative team is turning over every stone" to understand who did this and why.
The attack, which damaged an AT&T building, has continued to wreak havoc on cellphone service and police and hospital communications in several Southern states as the company worked to restore service.
The Associated Press contributed to this report.
Danielle Wallace, David Spunt
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