A Fitzroy restaurant will have to pay around $10,000 after becoming the first Victorian business fined for breaching coronavirus restrictions, as the number of COVID-19 cases in the state rises by nearly 100 — including four infants.

Key points: China Bar in Melbourne's inner-north was serving customers on the premises on Saturday night

China Bar in Melbourne's inner-north was serving customers on the premises on Saturday night According to the Chief Health Officer the infants diagnosed with COVID-19 do not appear to be a cluster

According to the Chief Health Officer the infants diagnosed with COVID-19 do not appear to be a cluster The State Government has also banned the sale of firearms for sporting and recreational shooters after the number of firearm permit applications doubled in the past week

Police Minister Lisa Neville also this morning put a temporary ban on additional access to firearms and ammunition for recreation and sporting shooters.

The moves came as Victorian health authorities confirmed another 96 coronavirus cases, taking the state's total to 917.

At a press conference on Tuesday afternoon, Chief Health Officer Brett Sutton said four of the new cases were pre-school-aged children — three cases in children aged under one year and a one-year-old — bringing the total number of pre-school-aged cases in Victoria to five.

Professor Sutton said it did not appear to be a cluster of cases and the advice on childcare centres staying open had not changed.

"There's no apparent linkage between them but that is being looked at at the moment," he said.

He said overwhelmingly for children under nine the illness was "very, very mild" and deaths were "virtually unheard of".

Health Minister Jenny Mikakos said all of the children were recovering in isolation with their families.

"One of the cases got it overseas," Ms Mikakos said.

"Investigations are continuing into the other three cases. I should stress it's not believed this is a cluster.

"It doesn't appear this is one childcare centre or one group of children all known to each other."

Concerns about trajectory of community transmission rate

The number of suspected community transmissions has increased by six to 32.

"The community transmission will be significant in a few days if we don't get on top of it," Professor Sutton said.

"We've seen a 25 per cent increase in a day. This is significant.

"We wouldn't want to see that trajectory ongoing."

Ms Mikakos added that six healthcare workers at Eastern Health had tested positive for COVID-19 but could not yet say if they were doctors, nurses or other staff.

In an email to staff, Eastern Health said that none of the six staff were severely unwell and they were currently self-isolating at home.

Box Hill Hospital, a part of Eastern Health, has introduced temperature checks on anyone entering the hospital. ( ABC News: Jessica Longbottom )

The ABC understands that at least one of the staff is a doctor.

"We've seen this in many countries around the world that our healthcare workers are at risk," Ms Mikakos said.

"Our healthcare services are alive to those risks, and they work incredibly hard to keep their staff and their patients safe."

Eastern Health introduced temperature testing at its hospitals on Tuesday, including Box Hill Hospital, following the positive tests.

Three health care workers at The Alfred and four at Werribee Mercy Hospital, in Melbourne's west, have also tested positive for the virus.

More than 45,000 tests have been conducted to date and 29 people are in hospital — including four patients in intensive care — while 291 people have recovered.

Federal Health Minister Greg Hunt said there were now 4,359 cases of coronavirus in Australia and 19 people had lost their lives.

Fifty people are in intensive care and 20 people are on ventilators.

'Sometimes it's the carrot and the stick'

On Monday, Victoria Police fined China Bar in Fitzroy $9,913 for breaching a directive that non-essential businesses should close.

Victoria Police Deputy Commissioner Shane Patton said the business had six staff working on Saturday serving customers who were drinking and eating on the premises.

"Sometimes it's the carrot and the stick and now we have a $10,000 stick," Deputy Commissioner Patton said.

China Bar is the first business to be fined under new restrictions. ( ABC News )

He said when questioned on Saturday night, the staff at the Fitzroy restaurant "weren't cooperative, they refused to say how long they had been open and they refused to state why they were open".

"Essentially a 'no comment' response," he said.

"It's the first time we've issued an infringement but it won't be the last. I can assure you.

"We've been fairly lenient, we've issued a lot of warnings but I think now the time for that has passed.

"Unless you've been living under a rock or unless you're an idiot, you're quite clear that the restrictions are there … so we are going to be enforcing them from today.

"Police [will] use discretion but that's going to be more the exception than the norm."

No fines yet for individuals

Victorians who are caught breaching other physical-distancing measures, such as the limits on people attending weddings or funerals, now face on-the-spot fines of $1,652.

The fines can be applied to anyone leaving the house for "non-essential reasons".

That means leaving for anything other than work, education, medical care, exercise or to get food and supplies.

The two-person limit in Victoria does not apply to people who live in the same house, and excludes workplaces and schools.

What can I do under the two-person rule? Take the kids to see their grandparents — No

Take the kids to see their grandparents — Have a tradie come to your house — Yes

Have a tradie come to your house — Two friends with babies go for a walk — No

Two friends with babies go for a walk — Drive with more than two people for work — No Source: Victorian Chief Health Officer Brett Sutton, ABC Radio Melbourne

Deputy Commissioner Patton said about 20 people weren't at home when police conducted spot checks.

"That's not unusual," he said, adding that they could be visiting a doctor.

He said people who "deliberately" breached isolation rules could be charged with offences under the Crimes Act.

"Conduct placing a person in danger of serious injury, which carries five imprisonment, or conduct placing a person in danger of death, which carries 10 years. These are serious indictable offences. We are open to considering that, these aren't idle threats," he said.

"It might be criminality that we're talking about."

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Firearm sales restricted during 'incredibly stressful time'

Explaining the firearms restrictions, Ms Neville said the Government was concerned by the increase in attempts to access firearms, adding the coronavirus pandemic had made it an "incredibly stressful time for people".

She said the number of attempts to access certain categories of firearms and ammunition had doubled in the past week from about 1,000 to 2,200.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 4 minutes 33 seconds 4 m 33 s Victorian Police Minister Lisa Neville said the restrictions on gun sales took effect immediately.

"We know there are pressures around family violence and also around work and people spending a lot of of time together," she said.

"This applies to sport and recreational users of firearms. It does not impact on primary producers or those who need it like security guards, prison guards, for example."

The ban on the sale of guns and ammunition takes effect immediately. ( ABC News: Sam Clark, file photo )

Shooters, Farmers and Fishers Party Victorian MP Jeff Bourman pointed out that gun licences were predicated on applicants having safe storage and described the move as "unmitigated bulls***".

"Do us the courtesy of admitting it's just another shafting of the most law abiding segment of society because it's easy," he said on Twitter.

Crime down overall but commercial burglaries and family violence up

Deputy Commissioner Patton said the police were continually reviewing crime rates.

He said there had been an overall decline in crime over the past week, but a "slight increase" in commercial burglaries and family violence, which he said police were "really focused on".

Family violence support services in Melbourne have told the ABC that some abusive men have been using the pandemic as a weapon against their partners in "horrendous" forms of abuse.

"We continue to monitor these areas and put resources into specific categories," Deputy Commissioner Patton said.

"We're going to be checking everywhere. And if we see carloads of youths driving around because it's fun to drive around together; $1,652 for each person in that car."

Supermarket, Kmart store, construction sites hit with cases

The Brandon Park Coles supermarket and attached Liquorland, in the south-eastern Melbourne suburb of Mulgrave, have been cleaned after two employees tested positive for the coronavirus, the supermarket giant said in a statement.

The company had confirmed with the Department of Health and Human Services that the store could continue to trade and the risk of transmission for customers and team members was "very low".

"The individuals need to remain isolated and their close contacts need to be followed up, but the settings themselves, if they're cleaned then they're not a risk to others," Professor Sutton said.

"I'm sure Coles has gone through a very thorough process of cleaning so that anyone passing through there subsequently is not at risk."

The two employees and those who had been in close contact with them have been ordered to self-isolate.

At Kmart at Chadstone Shopping Centre, two casual workers who were on duty on March 28 also tested positive to the virus. The store is closed while cleaning is being carried out.

Chadstone remains open with crowd-control measures in place, but at least half of the centre's shops are closed.

Simon Smith owns a confectionary and chocolate store at the centre and has decided to stay open.

He said business was so bad he needed "financially … to take the risk".

"I'm down to just one staff [member] and [I've asked her] if she's happy to come into Chadstone," he said.

"She's deciding to come in and help us."

Work has been suspended on the Melbourne Square apartment construction site in Southbank for at least 24 hours after the developer Multiplex was informed on Monday night that a worker had tested positive to COVID-19, the company's regional managing director Graham Cottam said.