Hampshire Police said a man in his 20s was arrested at the scene of the crash on suspicion of causing death by driving without due care and attention.
The double-crewed ambulance belonged to South Central Ambulance Service NHS Foundation Trust (SCAS) and was en route to Southampton General Hospital with the elderly patient.
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The 'situation is safe' and the suspect has been detained and removed from the scene, Dutch military police confirmed.
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A delayed thaw with the cold air