Four people were injured in the crash. Police were alerted about 12.35pm.
Three people received moderate injuries and one person received serious injuries, a police spokesman said.
At least three ambulances, police and Fire and Emergency NZ vehicles attended the accident.
The crash was at the intersection of SH1 and Cross St. It is believed a vehicle coming out of Cross St collided with a vehicle on SH1.
The northbound lane was blocked as a result, but the Waitaki River bridge remained open.