The ambulance driver involved in the fatal accident near Cambridge at 3.40 yesterday morning has now also died.
St John said it was devastated to be grieving the loss of one of its own.
The Patient Transfer Officer was returning to Rotorua from Hamilton when the accident happened. The attending nurse was also injured but is in a stable condition.
The head on collision happened on a stretch of State Highway One that has seen many crashes, and was once expected to be replaced by the Waikato Expressway.
Waikato Chamber of Commerce chief executive Don Good told Morning Report the crash should be a turning point, and the expressway extension should be prioritised by the government.
He spoke to Susie Ferguson.