The bomb squad has been called to Hanscom Air Force Base after potentially explosive material was found in a moving truck during a routine vehicle inspection.
Massachusetts State Police added that the department's air wing and bomb squad are on-scene. The state police Fusion Center is assisting with the investigation.
The "security concern" led Hanscom to "put response actions in place", including "a temporary closure of the base's Vandenberg (Rte 2A) Gate and evacuation of several nearby base facilities", Hanscom said in a statement.
All news helicopters have been told to vacate the air space over the base over to security concerns the truck poses, WHDH reported. The vehicle in question is a moving truck owned by Big Foot Moving out of Acton. "As of now, following the standard safety procedure, the gate has been evacuated". The truck has since been cleared, but some items that were removed will be taken to a special facility for testing.
The exit from Route 2A to the air base has been closed temporarily.
No injuries were reported during the incident.
Massachusetts Gov. Charlie Baker said he has been briefed on the situation, but he is not able to say much because the investigation is still ongoing.
Investigators eventually cleared the truck and its contents, which were delivering personal belongings to a new recruit at Hanscom Air Force Base in Bedford, about 20 miles (32 kilometers) outside Boston. The base spans land in Concord, Bedford and Lincoln. The adjacent Hanscom Field provides general aviation and charter service.