Police are looking for two women seen deliberately jumping in front of traffic on State High 1 north of Auckland, causing a serious crash which left seven people injured.
Police say a driver was forced to take evasive action and crossed the centre line, colliding head-on with another vehicle shortly after 8pm on Thursday near Warkworth.
Seven people were taken to Auckland City Hospital, and two remain there on Friday with moderate injuries.
Police say the women may have been hitchhiking. They are appealing for anyone who may have given them a ride or seen them to come forward.