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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A murky start to the day with some sunny spells, but plenty more rain to come!
Centre Jonathan Davies and fly-half Dan Biggar have been named in the Wales starting line-up for Sunday's encounter.
A blustery night with scattered, heavy showers. But there'll be some dry spells with clear skies.