A serious road traffic collision took place at 6.25pm on Thursday, July 19, on the unclassified road between Weekley and Grafton Underwood near Kettering.
The incident involved three vehicles, a silver Daewoo Matiz being driven by a 24-year-old woman, a silver Vauxhall Astra being driven by a 56-year-old man and a red Peugot 307 being driven by a 21-year-old man.
As a result of the collision the 24-year-old woman driver and her 28-year-old woman passenger were taken to Kettering General Hospital with serious injuries. The driver is expected to be transferred to John Radcliffe Hospital in Oxford.
The two other drivers received minor injuries.
Officers would like to speak to anyone who may have witnessed this incident.
Anyone with information or who witnessed this incident is asked to call the Drivewatch Hotline on 0800 174 615.