Rex Phillips from the NASUWT union, which represents a large number of teachers at Cwmcarn High School, says they are "shocked and concerned by what appears to be a very serious incident" at the school yesterday.
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A wet and windy day across Wales, but it should feel a little milder than it has done recently!
There'll be a few wintry showers over the hills tonight but these will ease to leave frost and ice in places.
Missed Wednesday's Wales at Six? You can catch up here.