Police are appealing for witnesses following a collision between a coach and a lorry on the A1 yesterday (Sunday).
It happened on the northbound carriageway at Diddington, south of Buckden, at around 5.30am.
The coach had been returning to Newcastle-upon-Tyne from London. 11 people suffered serious injuries and 35 suffered minor injuries. Two people remain in hospital.
Sergeant Gordon Murray said: "I would appeal for witnesses to the collision or anyone who saw the vehicles in the moments leading up to the incident."
Anyone with information should contact the roads policing unit on 101.
More top news
Members of Norwich's promotion winning squad say they've put to bed last year's relegation heartbreak after returning to the top flight.
A grieving father who thought the police were not doing enough to catch his son's killers has been tasered after threatening police.
Celebrities have taken to the social-networking site Twitter in light of Norwich City's success at Wembley.