A man using a metal detector in a heavily forested area off Route 1 in a North Shore town stumbled upon a rare discovery: dynamite and other explosives.

Rowley Police and the Massachusetts State Police Bomb Squad responded to a state-owned forest near the Newbury town line around 2:30 Thursday afternoon receiving the man called in to report the finding.

The discovery consisted of “a box of TNT and a small amount of plastic explosives buried in a metal container,” Rowley Acting Police Chief Stephen May said in a release Thursday evening.

“The box and the explosives appeared to have been in the ground for an undetermined number of years,” May said. “Due to the apparent age of the explosives and the amount of time they had been buried, no further investigative efforts are expected.”

Rowley Police called in the Massachusetts State Police Bomb Squad, which destroyed the explosives with a series of three blasts.

The rare finding, which also drew a response from the FBI and the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives, did not cause nearby homes and businesses to evacuate, May said.

That’s because the man found the explosives and TNT in a “remote part of town far away” from civilization.