All sixth form students at Victoria College have been told to go home after another case of coronavirus was confirmed at the school.
The government says the affected student is isolating at home, along with the rest of their household.
Sixth-formers have also gone home until the direct contacts of this student are found.
"The College has contacted parents with the relevant information and will remain open following advice from Environmental and Public Health.
"We are committed to supporting our students who have been impacted by the pandemic. Students who have to be at home due to Public Health guidelines will continue to receive school work online so that they can continue with their education."
All students in Years 11 to 13 now have to wear masks in school communal areas.
Three Victoria college pupils tested positive for the virus last week, with two others who go to the school diagnosed in the week before that.
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