Updated 15:52, 10 December 2012: More details on the incident
A 75-year-old patient has died after the ambulance she was travelling in crashed off a suspected icy road and ended up in a ditch.
The woman was pronounced dead at the scene after the ambulance left the A16 at Sibsey, near Boston, Lincolnshire in the early hours of Monday, less than three miles from the hospital.
Two male ambulance service staff, aged 52 and 62, were taken to Boston's Pilgrim Hospital and treated for minor injuries.
Investigations are ongoing into the incident, with one line of inquiry being the road conditions at the time.
It is believed the road may have been icy as temperatures dropped overnight.
East Midlands Ambulance Service (EMAS) offered their condolences to the family following the incident.
EMAS chief executive Phil Milligan said: "We offer our sincere condolences to the family and friends of the patient who died following this tragic incident."
In a statement, EMAS added: "One of our double-crewed ambulances was involved in a road traffic collision just before 3am this morning on the A16 Boston Road, Lincolnshire.
"The vehicle contained two of our ambulance crew and a patient who was being taken to hospital. No other vehicle was involved.
"The incident is subject to a police investigation and therefore it is not appropriate for us to make further comment at this time."
No details have been released about the patient or the reason for her being taken to hospital.
A Home Office pathologist is due to carry out a post-mortem examination on the woman on Tuesday.
Formal identification is due to take place on Wednesday, the police spokesman said.