Emergency responders on Long Island sawed off the roof and doors of a Mercedes-Benz to free critically ­injured driver Michelle McDonald, 29, after she collided with a trash-hauling truck early Friday.

McDonald, the mom of a 3-year-old boy, was alone in the car when the collision took place at about 6 a.m. near her home in Rocky Point.

She was pronounced dead at a local hospital. The truck driver, Brad Parnell, 43, who had just pulled out of a driveway, was not injured.