Ballacottier School is to remain closed until after Easter following a norovirus outbreak last week.
The Farmhill primary school was closed on Friday for deep cleaning before pupils were due to return today.
However, headteacher Carol Walsh has written to parents this morning, saying she wasn't satisfied with the standard of cleaning.
This morning, children were kept in the playground or sports hall before being sent home - and it's now been announced the school will remain closed until after the Easter holidays.
Alternative arrangements for children are being sought.
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