The five people involved in a horrific crash on the M40 that left one woman dead and two others critically injured were all members of one family, police have confirmed.

The incident occurred on the M40 northbound carriageway between Bicester and the Cherwell Valley Services at around 9.10am.

A grey Nissan Qashqai which was carrying the family from Coventry is reported to have left the carriageway at speed.

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A woman in her 60s died at the scene and a one-year-old boy is currently fighting for his life in hospital in Oxford.

Another woman in her 30s was seriously injured but is said to be in a critical but stable condition.

The two other occupants of the vehicle, a two-year-old girl and a man in his 30s received less serious injuries.

The man has since been discharged from hospital and the toddler continues to be treated in Oxford.

Police are currently unable to confirm the relationships of the victims, other than that they were all family members.

An air ambulance attended the scene and eyewitnesses reported seeing a large number of emergency vehicles.

The M40 between junctions nine and 10 was closed in both directions while the air ambulance arrived on scene.

The northbound carriageway was shut for most of the day to allow for an investigation to take.

This caused severe delays of up to 70 minutes on the M40 and surrounding road network.

The A34 heading towards Bicester, the B4030 westbound towards Middleton Stoney and the B430 northbound towards Middleton Stoney were particularly badly affected.

This was due to a diversion route put in place by National Highways as a result of the M40 closure.

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Thames Valley Police are now appealing for witnesses to the collision.

Senior investigating officer Sergeant Dominic Mahon of the Serious Collision Investigation Unit said: “I am appealing to anybody who was driving on the M40 at around the time of this collision to please get in touch with Thames Valley Police if you have witnessed this incident.

“I’d also ask anybody who was on the M40 between junctions 9 and 10 who has dash-cam to please check this and get in touch if it has captured the collision or the moments leading up to it.

“Tragically, one person has died of her injuries and two others have suffered critical injuries.

“Our thoughts are with all of those affected at this extremely difficult time.

“If you have any information or witnessed the collision, please contact us, either by making a report online or by calling 101, quoting incident reference 43230217234.”