Emergency services were called to the two-vehicle collision on the Riverton-Wallacetown Highway, near Price Rd, about 5.20pm today.
"Initial indicators are that there are serious injuries," a police spokeswoman said.
The highway is closed from Cumnock St in Wallacetown to Taramoa Rd, the New Zealand Transport Agency/Waka Kotahi advised.
Diversions are in place at Ryal Bush-Wallacetown Rd and Oporo Flat Rd.
The Serious Crash Unit has been advised.
Motorists were asked to avoid the area and expect delays.
- additional reporting Allied Media
Map: NZTA/Waka Kotahi
