In a statement on Cwmcarn High School's website, headteacher Jacqui Peplinski said "concerns were dealt with swiftly".
"There was no risk to any staff or learner and the relevant support services were contacted as a precautionary measure."
"Cwmcarn High is a caring and safe environment and we are committed to everyone’s safety."
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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.