The Romanian nationals would "skim" the details of bank cards in one country, then spend up large on those compromised accounts in the next country, before crossing borders again with a new batch of cloned cards.
The four men would never "skim and spend" in the same country, in order to keep one step ahead of the banks and law enforcement, but their globe-trotting heist came to an end in Auckland.
ASB staff discovered skimming devices and a pattern of suspicious transactions, leading undercover detectives to stake out several ATMs across Auckland.
Police arrested two skimmers in the act of withdrawing money and later seized 75 pieces of equipment used to commit forgery including pinhole cameras, blank cards, cell phone batteries and genuine parts of an ATM machine.
All up, they withdrew more than $100,000 in New Zealand with cloned cards stolen from overseas.
Daniel Bilea, Bogdan Irimia, Emanoil Pirjol and Dragos Dulhac were each jailed for two years last week after pleading guilty in the Auckland District Court to charges of possession of forgery equipment, obtaining a document and accessing a computer for dishonest purposes.
The skimming gang were travelling the world and living the "high-life" at parties and sports events in each country they visited, according to police.
"The only problem was they were funding it by skimming," said Detective Senior Sergeant Iain Chapman, the head of the Auckland City financial crime unit.
"Skimming in one country, then spending in the next country in a bid to avoid detection."
The Romanians travelled from the United Kingdom to New Zealand and booked tickets for Australia and the United States, said Chapman.
Skimming is the term for when electronic reading devices are placed over the card slot of the ATM, with a hidden camera trained on the keypad.
The devices secretly record the bank details of customers by scanning the magnetic stripe of the Eftpos card.
These details are then cloned on to blank cards, while the hidden camera footage gives them the corresponding PIN number, so they can make purchases or withdraw cash.
The Romanians arrived in New Zealand in March and April on visitor visas, telling immigration officials they were here for martial arts training.
In June, ASB raised the alarm with police to say cloned bank cards had been used 313 times at various ATM machines during May.
Undercover detectives staked out various ATMs in the North Shore and spotted three suspects - identified from CCTV footage - sitting in a car together in Takapuna.
They watched as Irimia tried to withdraw money with a cloned card before swooping to arrest him.
Bilea and Pirjol were arrested in the car carrying pieces of paper with handwritten PIN numbers, and more than $4000 and 58 blank cards were hidden inside a seat panel compartment.
The fourth member of the gang, Dulhac, tried to run from police when they turned up to the Mairangi Bay apartment where the Romanians were living.
He was later discovered hiding in a skip bin.
Inside the apartment, police found the tools of the skimming trade.
There were more than 100 blank cards and 75 pieces of equipment used for forgery including: 9 pinhole cameras, 4 card readers, 2 card-writing machines, 33 cell phone batteries, 15 data devices and genuine ATM parts such as card slots and keypads.
One of those hard drives had 96 hours of video footage of bank customers entering their PIN numbers at three different ATMs.
Card skimming gangs have regularly targeted New Zealand since the first case was identified 10 years ago.
And since the Romanians were arrested in June, Chapman said three others had been arrested and charged with similar offending.
He said police worked closely with the banks - in this case, ASB declined to comment - as well as border control authorities.
Nine passengers known or suspected to be credit card or ATM skimmers have been denied entry to the country since July last year, said a spokesman for Immigration New Zealand.
Holding passports from Bulgaria, Canada and Romania, five were denied boarding flights to New Zealand and four were turned around on arrival.
Customs also has the ability to seize and destroy any equipment they believe could be used for criminal activity.
