One person was taken to Waikato Hospital in a serious condition after falling from a moving vehicle in Te Kōwhai - a small rural town about 15km north-west of Hamilton.
St John said an ambulance attended the scene shortly after 6.30pm.
About 9.20pm, emergency crews were called to a crash on State Highway 67 in Granity on the West Coast.
One person was taken to Westport Hospital in a serious condition.
Just before 1.30am today, authorities received reports of a crash on Cust Rd in Cust, North Canterbury.
St John staff and a helicopter were dispatched to the site, where a person had suffered serious injuries.