The emergency unit at University Hospital of Wales is treating adults and children involved in the incident in Rhoose.
The unit has specialist procedures in place for dealing with serious incidents and those have been activated to care for those involved.
The priority now is treating those involved and supporting their families.
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Not too bad out there at the moment, with the heaviest of any showers easing during the first part of the night.
Sea Watch Foundation says it is investigating a reported but unconfirmed sighting of a killer whale off Ceredigion.
A man had to be freed this morning after an empty van rolled down the road and overturned, trapping him underneath.