The crash happened on the Parnassus Rd section of State Highway 1 just north of the town just after 2pm on Sunday.
Two of the injured were flown to Christchurch Hospital in separate rescue helicopters, St John said, one with serious injuries and the other with moderate injuries. Another person with moderate injuries was taken to hospital by ambulance.
Our thoughts are with the victims' families and friends.
What word do you associate most with the September 4 earthquake in Canterbury?
As part of Stuff's upcoming coverage of the 10th anniversary of the quake, we want to hear your memories of the day life changed dramatically for so many.
We're collecting your submissions to create a word cloud to be published on the 10th anniversary.
It may be a word that describes how your life or your community has changed, or one that takes you back to that very moment the earth shook on the morning of September 4, 2010.
To share the word you believe best sums up the 10 years since the quake, click here or email firstname.lastname@example.org
A reminder. The RANGIORA SUNDAY MARKET held in the BLAKE STREET CARPARK will be on from 9 am to 2 pm.
PLEASE use the COVID 19 tracing app. and observe social distancing
Great bargains for all from Plants, health products, hot food, handy person tools, books, puzzles, D V D "s and videos, garden tools, bikes, pet supplies, rustic bird feeders, handcrafts, woodcrafts, toys, adults and childrens clothing, potted daffodils, etc etc etc.
For the children we have THOMAS AND FRIENDS to operate on our large layout.
Don't forget the great food and coffee at FOOLS OF DESIRE at the market end of Conway lane.
Maree Roberts is a self-confessed workaholic, so when she decided to pack in a demanding career as a business development manager she needed something to fill in her time.
Roberts has lived in Kaiapoi for 30 years, and lost her first home in the Canterbury earthquakes.
She is committed to the region though, and has chosen to support the local community by starting a new retail venture. Read more here.