A spokesman said a woman in her 40s was trapped for about 40 minutes and had sustained life threatening injuries.
She was the sole driver in one of the vehicles and had been wearing a seatbelt, the spokesman said.
ROAD CLOSED - PAPAKURA-CLEVEDON RD, CLEVEDON - 6:45PM Due to a serious crash a section of Papakura-Clevedon Rd is NOW CLOSED between Tourist Rd and Clevedon-Takanini Rd. Please use an alternative route this evening. There will be no further updates tonight. ^TP pic.twitter.com/Qy2eQeMw2B