Two lanes have now reopened after an earlier crash on the M40 involving three vehicles.
The crash happened on the northbound stretch between Junction 3 A40 Knaves Beech (Loudwater) and Junction 4 A404 (High Wycombe Handy Cross Roundabout).
READ MORE
Bucks mum gets council payout after child custody blunders
Gerrards Cross crash: Car 'flips over several times after hitting road sign'
There were long delays earlier as emergency crews attended the scene.