The driver, a 42-year-old female ambulance technician, and the patient, an 88-year-old man, were pronounced dead at the scene.
A male crew member and a male relative of the patient remain in hospital both in a serious condition.
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Families across the South East are still anxiously waiting for news of their loved ones in Nepal.
Tuesday night's weather for the east of the region
Tuesday night's weather for the west of the region