A local former FBI agent and counterterrorism expert, James Conway, spoke with ABC13 to help answer questions on how an investigation like this will proceed.
Thwarting attacks, such as the one that happened in Nashville, is not easy, he said.
"It's extremely difficult. The FBI and law enforcement has thwarted hundreds of terrorist attacks before they happened, but this is something that didn't come up on the radar screen ahead of time," said Conway.
Authorities believe Friday's explosion in Nashville was intentional.
READ MORE: Human remains found near downtown Nashville explosion, police say
"So what they're looking at first and foremost right now: "Is this part of a larger plot? Could there be other bombs planted in the area?" he explained.
Conway says these are just a few of the many variables that investigators look into.
"The vehicle, its history, its owner, the explosives," he added.
WATCH | Video shows the aftermath of the explosion:
As of Friday evening, investigators had not released any details about a possible motive or intended target in connection to the explosion in Nashville.
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