Some of New Zealand's newest residents are Australian deportees experienced in meth trafficking, violence, and depraved online child sex offences.
Despite ongoing irritation at Australia dumping its unwanted inhabitants across the Tasman, a migration expert says there's not much New Zealand can do to stop the flood.
More than two dozen criminals were kicked out of Australia last week, barely a fortnight after the deportation of another 28 men, including two with outlaw motorcycle gang links.
One of the new deportees is a paedophile jailed for impersonating pop star Justin Bieber to trick girls as young as 12 into sending sexually explicit pictures.
According to News Corp, he is Kent Andrew Garrett, a Melbourne man in his late 40s.
Australian court documents show IT professional Garrett, also known as Orson Kent, admitted 29 charges including accessing and soliciting child abuse material in 2014.
He emigrated from New Zealand in 2007 to pursue opportunities in IT, The Age newspaper previously reported.
Most of the new deportees are known as 501s, after getting visas cancelled for failing the character test under section 501 of Australia's Migration Act.
Migration expert Professor Paul Spoonley said deporting Kiwi-born criminals saved Australian authorities huge money.
But New Zealand society and transtasman relations paid the price.
Spoonley, from Massey University, said 501s had often lived in Australia for many years and arrived in New Zealand with no support networks.
Sometimes the only networks were criminal fraternities.
"Australia's exporting its criminals, but also its gangs to New Zealand," Spoonley said.
"Then we get the Comancheros and others beginning to appear in New Zealand."
"New Zealand governments of various persuasions have tried to persuade the Australian Government to take a different line, and it's failed miserably."
Before 2001, New Zealand citizens in Australia on special category visas could access social security and get Australian citizenship without becoming permanent residents.
"The different treatment of New Zealanders began in 2001 and then of course, the 501s were really adding insult to injury," Spoonley said.
'It's both disappointing and a major threat to bilateral relations."
But he said apart from attempts at diplomacy or persuasion, it was hard to avoid taking back Australia's unwanted convicts.
"All countries have the right to deport citizens of other countries if they commit criminal offences - but the numbers here are significant."
More than 1000 people were deported in the two years to March 2018 alone.
Deportations stopped for no pandemic, with multiple 501 flights landing in Auckland this year.
A Managed Isolation and Quarantine spokeswoman said since mid-July, flights of deportees arrived with deportees completing their fortnight's isolation at a dedicated central Auckland facility.
The agency wouldn't say which location was used but some 501s are known to have stayed at the Ramada on Auckland's Federal St.
The agency said more than 75,000 returnees had been through MIQ facilities and only a small number were deportees.
It wasn't immediately clear when the next planeload of deportees was due to land.