Passengers on a flight from Melbourne to Sydney disembarked without being screened by NSW Health officials on Tuesday night, in a major breach of the state’s coronavirus protocols.

A leaked email from Sydney Airport claims Jetstar breached NSW government health orders by allowing travellers on flight JQ520, which landed at 6.53pm, to get off without being checked.

“The final JQ flight arrived and staff enabled disembarkation without NSW Health and police in attendance, breaching the arrivals screening protocols,” the email read.

NSW Health authorities are trying to track down at least a third of the 48 passengers who were on the flight.

The breach comes amid news a Victorian teenager tested positive to the coronavirus while holidaying in NSW after a bungle by health authorities.

Elsewhere, three new cases of coronavirus were confirmed in the ACT, breaking Canberra’s month-long bill of health.

The infections are all from the same household and linked to the Victorian outbreak.

The ACT’s Chief Minister Andrew Barr has signalled a slowdown in easing restrictions, which was planned for later this week.

Victoria confirmed 134 new coronavirus cases on Wednesday, as fears grow Melbourne’s outbreak will cross state borders.

Returning passengers required to self-isolate

On Tuesday, NSW introduced new laws that banned anyone from greater Melbourne travelling to the state except under “exceptional circumstances”, such as accessing urgent medical care or fulfilling legal obligations.

But all the passengers on the Jetstar plane – who would be required to self-isolate for two weeks – were allowed into Sydney without scrutiny.

Screening includes temperature checks and health questions. The traveller’s home address in Victoria is verified, and anyone who appears symptomatic is tested for COVID-19.

NSW chief health officer Kerry Chant confirmed there was “an issue” at the airport.

“The airport has now put in protocols to ensure that the health teams are there and able to do the screening, and no one is allowed to disembark before that happens,” she said.

“All of those individuals are known, obviously you get tickets when you’re on a plane.

“e are in the process of tracing them up – if anyone is found to have travelled in breach of any orders we’ll refer them to police and take the appropriate action, depending on whether anyone is symptomatic, to ensure the community is protected.”

Jetstar said it had “refined” its disembarkation procedures following the incident.

“We assisted by locating passengers in the terminal who had disembarked without being screened and provided the aircraft manifest to the department to assist them in contacting passengers,” a spokesperson said.

Jetstar also said Victoria Health performed temperature and ID checks on passengers before they left Victoria.

From Wednesday, restrictions tightened further and all Victorians are banned from travelling to NSW unless they live in a border community or qualify for an “exceptional circumstances” exemption.

Anyone caught crossing the border illegally faces a fine of up to $11,000 or six months in jail.

The email leaked to the ABC said three flights had arrived in Sydney from Melbourne in close succession late on Tuesday.

“Coincidentally, there was a media presence that captured the entire event unfolding and this may attract some attention over the next 24 hours,” it read.

Authorities have conceded there will be some flexibility in the first 72 hours of the border closure.

Further south in the border community of Albury-Wodonga, some people who could not access a permit were still being allowed to cross the border if they could prove they were exempt.

Earlier this week, NSW Health Minister Brad Hazzard said mandatory screening would apply to all passengers arriving from Victoria at Sydney Airport and at Central Station.

“Any passengers who display any COVID-19 symptoms, no matter how mild, are tested for the virus and directed to self-isolate,” he said.

“Any passenger who is identified as coming from a hotspot and does not meet the very strict eligibility for travel is directed to NSW Police officers.”

-with agencies