West Sussex County Council said the decision was taken to close Bersted Green Primary School, in Bognor Regis, on Friday (December 11), 'following a number of confirmed Covid-19 cases'.
This came following advice from Public Health England, the council said.
A spokesperson said the school would be closed until 2021, adding: "Parents and carers were informed by email and text message on Friday.
"We understand this will be concerning to families and appreciate their cooperation and understanding."
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