Two young people in the car were also taken to hospital to be treated for moderate injuries.
The Serious Crash Unit closed the road yesterday to complete a scene examination, and enquiries into the circumstances of the crash are ongoing.
Yesterday, a Fire and Emergency New Zealand spokesperson said they received a call at 3.30pm about a crash between a car and a motorcycle in central Hamilton.
A Hato Hone St John spokesperson said they responded to the crash, and four patients were transported to Waikato Hospital in a moderate condition.
A reporter saw at least 10 police cars near the scene at the intersection of Willoughby and Mill Sts.
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