Police searched his vehicle and found one glass pipe in the driver's side door, and another in a storage compartment. Then, they spotted the grenade.
The man told deputies he had cleaned out a military veteran's home and found the grenade. He said he wasn't sure whether it was active or not.
Deputies closed down a section of the roadway and asked the nearby St. Johns County Sheriff's Office for help with the grenade. It was removed from the truck and detonated.
A records check turned up the man's criminal history in Florida and Georgia, including burglary, rape, armed robbery forgery, grand theft, battery and giving a false name to law enforcement, officials said.
“Here’s a prime example of how deputies never know what a traffic stop may turn into,” Flagler County Sheriff Rick Staly said. “This idiot is lucky he did not blow himself or his truck up."
He was arrested and charged with driving with an expired license and possession of drug paraphernalia. An investigation is continuing on the grenade and more charges are possible, the sheriff said.