The collision on the A142, near Mepal, was reported to police at about 10.40pm on Sunday and involved a silver Renault Megane and a silver Renault Clio.
The head-on collision left the drivers with serious injuries.
The Megane was being driven by a 20-year-old man from Willingham, while the driver of the Clio was a 24-year-old man from Little Downham.
Both drivers suffered serious injuries and are being treated at Addenbrooke’s Hospital, in Cambridge. No other people were involved.
Sergeant Mark Atkins, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: “I would like to hear from anyone who may have seen either the Megane or the Clio in the build-up to this collision.”
Anyone with information about the collision or with dashcam footage, should contact police on 101 or contact the online the online webchat service quoting reference 527 of Sunday 10 July.
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