*4PM UPDATE: ONE WOMAN HAS BEEN KILLED.
Please note: State police say the accident took place in Southboro.
(NECN: Southboro, Mass.) - Massachusetts State Police have confirmed that a woman has died in the serious cash on I-495 Southbound in Southboro Friday afternoon, which closed down all four lanes on the highway.
A front-end loader being towed by a construction vehicle rolled over and landed on a car with four occupants, trapping them, said police.
The crash is considered very serious and could possibly involve fatalities.
Emergency personnel are working to clear the scene and have closed off traffic. Stay with NECN and NECN.com for more details on this developing news.