The patient survived the crash initially, but died after arriving at Milford Regional Medical Center, said Milford Police Deputy Chief Jim Heron. One of two paramedics in the ambulance received minor injuries in the crash, he said.
The woman was identified by police as Karen Scott, 58, of Upton. She was being transported by the Community EMS ambulance after undergoing a medical treatment at a nearby clinic, said Milford Police Sgt. John Sanchioni.
An initial investigation determined a woman driving a Mercedes sedan failed to stop at the stop sign at Green Street and Route 140, and traveled into the path of the ambulance, which was heading north, toward the hospital, Heron said.
The ambulance was spun around and flipped over before coming to rest against a guard rail near the Green Street Auto Spa. The Mercedes came to rest across Route 140, on Green Street.
The paramedic in the back of the ambulance with the female patient was injured, but the injuries were described as minor. The paramedic driving the ambulance was not hurt, Heron said.
He did not know if the ambulance was traveling with activated emergency lights or a siren. The ambulance was heading for Milford Regional Medical Center at the time of the crash.
The paramedics are employed by Marlborough-based Community EMS, a private company under contract to the town of Milford. In a statement, the company president on Tuesday expressed concern for the family and friends of the patient, and said the company was cooperating with authorities.
"An initial investigation has determined that the driver of the other vehicle failed to stop for a posted stop sign and struck the rear of our Ambulance causing it to flip and roll over before coming to rest against a guard rail," wrote Randy Jusseaume.
"At this early stage of the investigation, we have no additional information available other than what has been reported by the local authorities," he wrote. "This is an active and ongoing investigation and we fully intend to assist and cooperate with all of the involved authorities."As a result of the crash and the investigation, Route 140 was shut down in both directions, with police diverting traffic at the Route 16 intersection, and at Green Street.
The Worcester County District Attorney's Office is investigating the crash.
The woman driving the Mercedes sedan, Lisa Zemack of Framingham, will be charged with a civil violation related to not stopping at the stop sign, Sanchioni said.
No decision has been made on whether additional charges will be brought, said Police Chief Thomas O'Loughlin. The investigation is being handled by the Central Massachusetts Law Enforcement Crash Reconstruction team.
The intersection has had several serious crashes in the past several months, including one involving a Milford police officer in August. The police cruiser was struck while traveling north on Rte. 140 when a driver, heading west on Green Street, failed to stop at the stop sign. The officer was injured but has since recovered and returned to work.
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