UPDATE, 11:30 a.m.: The ramp from Route 290 eastbound to 495 northbound remains closed after the Thursday morning tractor-trailer rollover.
The crash, reported earlier as being in Northborough, was actually in Marlborough, said police.
The driver was extricated by firefighters but was not injured, said a release. The trailer was hauling food, which has been condemned by the local board of health.
The ramp is expected to be closed until approximately 1 p.m. as cleanup and the investigation continue.
Troopers from the State Police Barracks in Leominster and the State Police Commercial Motor Vehicle Enforcement Section are on-scene.
Massachusetts State Police and rescue crews are on the scene of a tractor trailer rollover on the ramp between Route 290 to Route 495 northbound in Northborough.
The crash happened shortly before 9 a.m., at which time police began diverting traffic approaching 495 North, on to 495 South and ultimately Route 20 in Marlborough.
The just off the westbound exit was packed with motorists adjusting their travel routes.
The operator of the truck was trapped at one point, said police, but did not appear to be seriously injured.
Information as to the cause of this accident had not been released as of this post.
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