Parents have been told to take their kids home from a popular school in Sydney's east where there has been a confirmed coronavirus case.
It comes just one day after students across the state returned to classrooms full-time.
Parents at Waverley College have been asked to collect their children from the school.
The school buildings will be subject to a deep clean and closed for a period of time, a school representative told Sydney's Daily Telegraph.
Close contacts of the boy were being notified and asked to self-isolate. It's understood the Year 7 student is a boy.
Around 1400 students go to the non-selective college from early learning, and Year 5 to Year 12 across two campuses.
This all comes after a student tested positive at St Ignatius College, Riverview last week.
Students in New South Wales returned to the classroom yesterday two months after Covid-19 restrictions forced around 800,000 public school children to study remotely.
Some independent and Catholic schools also returned on Monday while others were working towards a June 1 return date.
NSW Education Minister Sarah Mitchell said the return to school had gone very well.
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Speaking to Newstalk ZB's Mike Hosking this morning, director-general of health Ashley Bloomfield said that work is happening "apace" on a possible transtasman travel bubble with Australia.
Asked if he would travel to Australia today - like another health expert, Michael Baker, has said he would do - Bloomfield told Newstalk ZB's Mike Hosking that he had no trips planned.
"The risk in Australia is low, particularly in some parts of Australia, it is low in New Zealand. Rest assured there is work happening apace to see how we can potentially open that border up and enable travel between the two countries."
While no timeframe has been given on when borders might freed up, Jacinda Ardern earlier told media that Australia would need to sort out some internal issues first.
"The states haven't opened up to each other yet," she told RNZ. "Obviously I would expect to see some of those issues resolved before we'd see them necessarily opening up to New Zealand and you can understand why.
"People want to be able to travel internally in Australia before they'd expect to be able to come across the ditch."
Speaking later, she softened her language, saying the "most likely sequencing" is state borders opening up first.
"I imagine they'll want to see those issues resolved around their domestic border, most likely first, that's my expectation."
-Additional reporting, NZ Herald