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.
More top news
There'll be bracing winds and heavy showers this afternoon and expect a wet and windy start on Monday morning.
Carl Edwards and guests look back at the week's events in the latest edition of Newsweek Wales.
A Yellow Warning has been issued by the Met Office as gale force winds and showery rain affect areas across Wales.