A teenager has been charged with manufacturing a firebomb after Roanoke County police Thursday found materials for it in a vehicle at William Byrd High School, officials said.

Chuck Lionberger, a spokesman for Roanoke County Public Schools, said the bomb was found during a routine drug search and was removed from campus.

According to Roanoke County Police, the materials were household items, some of which may have been flammable, but the device's components were partially disassembled. They said the device posed no threat to students or staff.

Police charged a 17-year-old male in connection with the device and materials, but said he is not a student of the school and was not on school property. It remains unclear when and where he was located.

-- Neil Harvey