Two people suffered life-threatening injuries and nine others were hurt when a double-decker bus crashed into a hedge.
The driver and 18 passengers were on the Stagecoach bus when it crashed at Oakley, near Basingstoke, Hampshire, at about 1200hrs.
Three people have been seriously hurt and the others suffered minor injuries.
No other vehicles were involved in the crash.
The two most seriously injured people have been taken to the major trauma centre at University Hospital Southampton, South Central Ambulance Service (SCAS) said.
Three unaccompanied children were not hurt.
Bus operator Stagecoach said it believed the bus "remained upright at all times but that a number of people have been injured, including our driver".
"Safety is our absolute priority and we will assist the police fully in their investigation into the circumstances around this incident."
