Police are appealing for witnesses to a road traffic collision on the A422 near Buckingham on Wednesday.
A red Ford Focus and a silver Lexus IS200 were involved in the collision on the A422 Stratford Road between Buckingham and Thornton, near the junction for Maids Moreton, at 6.45pm.
Both drivers, a woman in her fifties in the Ford and a man in his twenties in the Lexus, sustained serious injuries and remain at the John Radcliffe Hospital in a critical but stable condition.
No arrests have been made at this stage of the investigation.
PC Thomas Walker, of the Joint Operations Roads Policing Unit, said: “We are appealing for any witnesses to this collision, whereby a man and a woman have sustained serious injuries, to please come forward.
“We would also like to know if anyone has any dash cam footage of the incident or the moments beforehand and to send it to us if you do.
“Anyone who can help should call 101 or by making a report on our website, quoting reference number 43230366926.”
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