UPDATE, 10.10am: Seven new cases of COVID-19 have been diagnosed in Victoria, including a Keilor Downs College student in north-west Melbourne.
Premier Daniel Andrews said three cases were found in routine testing, two were people in hotel quarantine after returning from overseas while two are still under investigation.
The student from Keilor Downs College is part of a family cluster of five announced on Thursday.
It comes just days after senior students returned to classrooms for the first time this week, after six weeks of learning at home.
"He was probably infectious on site at the school only on (Tuesday) May 26," Victorian chief medical officer Brett Sutton said.
Professor Sutton said there was no evidence of a link between the student and the staff member who tested positive last Friday, as the teacher had no exposure to the school site.
The school has been closed for cleaning.
Professor Sutton said a mobile testing site will be established in Keilor Downs.
The premier warned that from Monday, the state government would have the power to force people and businesses to work from home.
Breaching those guidelines could lead to fines.
"If an office that had currently, say, 80 per cent of their staff working from home then say 'oh well, we'll just ignore the chief health officer and we will have everybody come back Monday,' then they would be in breach of the public health orders," Mr Andrews said.
"That means there will now be a clear and shared responsibility between workers and their bosses. For employees, that means an obligation to keep working from home. And for employers, an obligation to support them in doing so..
"As we've said from the start, our actions will always be guided by evidence. Right now, we can't have the usual number of people on our trains, trams and buses - it just isn't safe.
"We don't yet have a timeline on when this might change, or how we might be able to get back to work as normal.
"For now, we're saying this will be in place until at least the end of June, but it may well be longer. As always, that will depend on the advice of our chief health officer.
"If you've been working from home -you must keep working from home."
At 8.40am: Federal minister Peter Dutton has raised the possibility of extending the JobKeeper wage subsidy beyond September.
The home affairs minister indicated the federal government had room to move to help Australians financially survive the coronavirus pandemic.
"I think we are flexible and we will look at the way in which we could help businesses and people get back to a normal way of life," he said on Friday morning.
"But there's a way to go yet as we know.
"Ultimately that's a decision for the PM and the treasurer."
Treasurer Josh Frydenberg said he recognised that additional support would be needed for some sectors that were slower to recover.
"It's not just always about JobKeeper, it's also about what other support packages and initiatives you can undertake in various sectors," he said.
The federal government budgeted $130 billion for JobKeeper, but the cost of the $1500 a fortnight subsidy was overestimated to the tune of $60 billion which has given the government room to move.
Earlier: About 56,000 sheep bound for the Middle East may haver to be transported on a second ship after livestiock vessel Al Kuwait became stranded in Fremantle due to an outbreak of coronavirus among the crew.
The Al Kuwait docked in Fremantle last Friday with almost 50 crew members on board and 12 positive COVID-19 tests had been confirmed by yesterday.
Most of the crew is now in hotel quarantine, while 10 remains on board to mman the ship.
Health officials said port workers who boarded the vessel, including a Fremantle Port Authority pilot and a trainee who steered the ship into harbour, are self-isolating at home while awaiting their test results.
But, exporting of the sheep is up in the air with the northern summer live export ban beginning on Monday.
Any delay will require a federal agriculture department exemption.
WA Agriculture Minister Alannah MacTiernan said negotiations were under way to use the Awassi Express, which is not far off Fremantle.
That vessel sparked the summer ban following outrage over mass sheep heat deaths in 2017 .
"Hopefully we can get that arrangement," Ms MacTiernan said yesterday.
- With AAP
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