A disposal team from Fort Hood removed an apparent home-made bomb early Friday after police discovered it inside a pickup truck during a routine traffic stop at a Waco intersection.
Waco police Sgt. W. Patrick Swanton told television station KWTX the package was armed and included a hand grenade and other materials.
The truck driver, 52-year-old Joseph Gaynor, was arrested. He's facing charges for the incident, including possession of a prohibited weapon or explosive device, driving with an invalid license and a drug count, records show. He also has two traffic violations.
Bond wasn't immediately set and authorities weren't sure if he had an attorney.
Authorities shut down the scene a block from the Waco Independent School District bus lot for several hours overnight as explosive experts from the Army base worked to decide if it was safer to take the device to Fort Hood or detonate it in Waco.
Police used a robotic camera to inspect the package before deciding to call in help from Fort Hood, about an hour away.
Investigators said the package was round, wrapped with tape and had wires attached to it.
Swanton said authorities didn't know Gaynor's intentions.
The federal Bureau of Alcohol, Tobacco, Firearms and Explosives also has been notified and will be interviewing Gaynor, Swanton said.