Victoria has confirmed 24 more local COVID-19 cases as the state’s police union boss says officers don’t want to enforce a ban on playgrounds.

The health department on Wednesday confirmed 20 of the new cases were linked to known outbreaks, while the remaining four were mystery infections.

Eighteen were in isolation for their entire infectious period.

Some 39,832 tests were processed in the 24 hours to Wednesday morning, while 27,173 Victorians received a vaccine dose at a state-run hub.

There are 246 active cases in the state.

Tweet from @VicGovDH

It came as Police Association Victoria Secretary Wayne Gatt expressed concern about the lasting effect of enforcing “unpopular and deeply restrictive rules for a prolonged period” on community views of the force.

“Police are now tasked with enforcing a curfew that no one has welcomed, and to prevent families from going to playgrounds that bring them joy,” he wrote in an opinion piece in the Herald Sun on Wednesday.

“I hope that our members do not have to ever actively enforce this ban on playgrounds.”

About 50 children in the state aged 10 and under are fighting the virus, including a child in intensive care who is in a stable condition.

• See a full list of Victorian exposure sites here

Chief health officer Brett Sutton said on Tuesday his team was probing a potential case of playground transmission, along with a “more definitive” link between students from different classes who walked home together.

Outdoor playgrounds, basketball hoops, skate parks and exercise equipment were closed and the city’s 9pm to 5am curfew reimposed this week, in a bid to contain the state’s worsening Delta variant outbreaks.

There are now more than 520 exposure sites in Victoria, including a Jacana skate park that was added as a tier two exposure site on Tuesday night.

Late-night weekend public transport has also been cancelled across Melbourne as virus rules tighten. There will be no trains, trams or buses will between 1-5am on Saturdays and 1-6am on Sundays for the next two weeks.

The state government has defended the cancellation, saying it was also imposed during last year’s second wave of COVID.

Melbourne is 13 days into its sixth lockdown, which was extended on Monday until September 2.

Meanwhile, health authorities are pleading for residents of south-east Melbourne to get tested over fears the virus is circulating undetected.

-with AAP