Disturbing footage has emerged of throngs of international arrivals lined up at Sydney airport on Thursday morning, in direct defiance of social distancing rules  designed to stem the spread of the coronavirus.

The footage shows confused crowds of returning travellers being herded close together in long queues that do not meet strict new rules imposed as the virus pandemic spreads.

Twitter user Sally Prosser, who posted the footage, who told the ABC it was filmed by a family member.

“I just feel like it was a real kick in the guts to everyone out there doing the right thing,” she said.

“At the front line, there’s nothing, there’s no one even encouraging people to stand apart.”

Tweet from @sally_prosser

Australia’s borders are officially closed to foreign travellers, and Australians cannot travel overseas. However, there are still some flights for Australian citizens and permanent residents returning home as COVID-19 spreads across the world.

The public sector union, which represents biosecurity and Australian Border Force officers, said the disturbing scenes in Sydney were due to unplanned and badly communicated changes.

Changes introduced on Thursday morning meant every returning passenger is now tested for COVID-19.

“The testing space is too small for all passengers, and disembarking is not being staggered to allow for social distancing,” the union said.

CPSU deputy national president Brooke Muscat-Bentley said the crowds were a direct failure of government.

“It is astonishing that the government is telling the nation to social distance and take the utmost precautions but cannot take steps to assure us at our border,” she said.

“This is a failure of planning, just like we have seen with Services Australia this week. The government has known what was coming, but have just been unable or unwilling to prepare for it.”

Sydney Airport said in a statement it had since placed security guards in its terminals to “remind people of their obligations”.

It said its priority in any crisis was the health and safety of its staff and that of everyone who came to the airport.

The footage comes amid a blame game between border force and NSW Health about which was responsible for letting sick passengers off the Ruby Princess cruise ship in Sydney last week.

More than 130 passengers from the vessel have tested positive for coronavirus, including a 77-year-old woman who died earlier this week.

Another cruise passenger died in Townsville on Wednesday, and two more in Victoria on Thursday – bringing Australia’s coronavirus toll to 11.

NSW Police Commissioner Mick Fuller has now been given responsibility for controlling and quarantining cruise ships and other vessels.

Labor’s Kristina Keneally said that left Home Affairs Minister Peter Dutton with questions to answer.

“The NSW Police are taking over cruise ship arrivals. Airport queues are violating social distancing rules. The Australian Border Force is getting mixed messages and directions,” she said.

“The Minister for Home Affairs needs to get on top of our borders, today.”