A portion of Route 16 in Chelsea, Massachusetts was shut down to traffic after a grenade was found in an occupied building on Monday morning.
The grenade was discovered in a building at 266 Revere Beach Parkway sometime after 11 a.m. by emergency personnel performing a well-being check.
Chelsea Police said the 30-unit building has been evacuated and the road has been shut down as a precaution on the westbound side. Surrounding residences are also expected to be evacuated.
The Massachusetts State Police Bomb Squad responded to the scene.
Fire officials said the grenade was determined to be a dumy or a souvenir, but two canisters of black powder were also found inside the building that were labeled "explosive." They said the canisters are being taken to Rumney Marsh in Revere.
The investigation is ongoing and the scene remains active.
No further information was immediately available.