BOSTON (Reuters) – Massachusetts State Police said on Thursday they were investigating a suspicious truck stopped at the gates of Hanscom Air Force Base after an initial screening of the vehicle indicated signs of possibly hazardous material.

Parts of the base were evacuated but no injuries were reported, base officials said in a statement. The incident began at about 9 a.m. EDT (1300 GMT) when base security became concerned about the truck at a gate during a routine inspection.

The State Police bomb squad and a State Police helicopter went to the scene at the base, located about 15 miles (24 km)northwest of Boston.

About 10,000 people, including military staff and civilians, work at the 846-acre (342-hectare) site in Bedford, Massachusetts, which is home to units overseeing acquisitions, cyber security and some nuclear operations.

Live aerial footage showed a large truck with “BigFoot Moving & Storage” emblazoned on the side stopped near the base’s gate with an armored military vehicle parked nearby. Police said they had set up a 1,500-foot (457-meter) perimeter around the truck. ”

A person who answered the phone at the moving company and declined to give her name said that she was aware of the truck’s presence at the base but had no details as to what was in it.

The nearby L.G. Hanscom Field airport, which caters to small planes, remained open, the Bedford Police Department said on Twitter.

(Reporting by Scott Malone; Editing by Jeffrey Benkoe and Gabriella Borter)