Police say nine people have been taken to hospital following this morning's collision in Rhoose - four with 'significant injuries'.
Four of the nine casualties are described as having significant injuries.
An Audi car overturned outside Rhws Primary School injuring four adults and five children, who have been taken to the University Hospital of Wales, Cardiff, and the Princess of Wales Hospital, Bridgend.
The age and sexes of those involved have not been confirmed.
The 61-year-old male driver of the vehicle, who is one of the nine casualties, is assisting police with enquiries.
At this stage the collision is not believed to be a deliberate act.
Emergency services are at the scene and the road remains closed.
Officers are asking anyone who witnessed the collision, or who gave assistance, to contact the South Wales Police Serious Collision Investigation Unit using the 101 number.
Police added the school, which is open, is currently contacting pupils' parents.
The Vale of Glamorgan Council is offering support to both school and pupils.
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