Three separate threats were allegedly made to Cwm Glas Primary School in Winch Wen, Gwyrosydd Primary School and Townhill Primary School.
Cwm Glas Primary was locked down for a short period on Monday 18 March over the malicious communications threats.
Chief Inspector Lindsey Sweeney from South Wales Police said: “We take the communications extremely seriously and as a result of our investigations a 21-year-old man is currently in police custody, having been arrested on suspicion of making threats.
“No objects of concern have been located, no-one was harmed, and an investigation is on-going.
“All schools are open as normal and our local PCSOs and Schools officers will continue to provide reassurance and support throughout the day.
“Those affected are thanked for their cooperation and we will continue to provide updates to our partners in education as the investigation progresses.”
(Lead image: Swansea Council)
