A male passenger has been taken by air ambulance to the John Radcliffe hospital with serious leg injuries after an accident on the M40 this morning.
Two vehicles travelling northbound went into a central reservation between J4 (High Wycombe Handy Cross Roundabout) and J5 (Stokenchurch) at about 8am.
All lanes have now reopened.
All traffic between Stokenchurch and the roundabout - about seven miles - was blocked, while southbound traffic had been stopped for the air ambulance.
The Oxford Tube tweeted to warn passengers of disruptions to services.
The Oxford Bus Company also said they were looking to divert their X90 and Airline services.
South Central Ambulance Service spokeswoman Michelle Archer confirmed a person was taken to the hospital with serious leg injuries.
SERVICE UPDATE: We are currently experiencing heavy delays Oxford bound due to a road traffic incident. https://t.co/THcy9lYGcL
— Oxford Tube (@Oxford_Tube) February 19, 2016
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