A coach with 35 passengers on board overturned as it left a motorway, police said.
The driver and 33 passengers were not thought to be seriously injured and were taken to hospital as a precaution, while two others remained at the scene being treated, Thames Valley Police said.
The single-deck vehicle turned on its side just before 11pm on Saturday at the top of the north-bound exit of the M40’s junction seven, near Thame in Oxfordshire.
No details of any injuries were currently available, but those who were taken to hospital were walking around, a police spokeswoman said.
No other vehicle was involved in the incident, she added.
The 33 passengers and driver were taken to John Radcliffe Hospital in Oxford.
Police have closed the north-bound slip road at junction seven while they investigate what happened, but the motorway is open in both directions.