Soil scientists surveying a densely wooded area of Person County near Roxboro on Monday discovered a cache of pipe bombs, the sheriff's office said.
The FBI is investigating a "person of interest" in connection with the bombs, according to ABC11. No arrest had been announced in the case as of about Wednesday afternoon.
The sheriff's office requested assistance from a Durham County Sheriff's Office bomb squad and during a three-day search, crews found 30 active, homemade PVC-style pipes filled with explosive materials in an area off Lucy Garrett Road, according to ABC11.
"They were not armed where they were ready to fire but they could have been armed very quickly," Person County Sheriff Dewey Jones said, according to CBS17.
All of the bombs were destroyed.
The suspect is a "preparing for doomsday type of person," Jones said, according to CBS17. "He very much had a lot of knowledge on what he was doing and how he was doing it."
Jones told ABC11 that he does not believe the bombs are an act of terrorism.
Jones told The Courier-Times that some of the devices were small, about an inch in diameter, while others were larger, closer to three or four inches in diameter. Jones said he was unsure who owns the land the bombs were found on.
Law enforcement notified about 20 neighbors and at least three residents were evacuated on Wednesday, according to ABC11. The residents have since been allowed to return home.
Jones said bomb-detecting dogs were being used in the area to check for more devices.
"We just want to make sure that we don't leave anything out here," he said, according to CBS17. "We're going to do the best that we can to get everything out of the area so nobody is in any danger."