Shocking dashcam footage shows a car towing a caravan driving the wrong way down the M40 just moments before it was involved in a major crash. 

The video, which was captured just seconds before the car was involved in a crash with two other vehicles on the northbound carriageway, shows other drivers diving out of the way as the car comes towards them in the fast lane. 

Shocked eyewitnesses say the car had "foreign plates" but no details have officially been released by Thames Valley Police. 

Officers were alerted to the incident just after 4pm on Monday as the car and caravan were travelling southbound on the northbound carriageway between junction 6 and 7.