The Easter break horrified more than 60 Auckland bank depositors after discovering that money was taken from their account in the past two days, and a scam operation in Canada may be involved.

Banks have been looking into complaints from depositors, with Westpac spokesman Chris Mirams saying an estimated 30 credit and debit card customers reported their money had been drawn at ATMs in Canada.

BNZ spokeswoman Erica Lloyd told Dominon Post about 30 Eftpos and flexi-debit customers had lost money from their accounts over the Easter weekend.

Dominion Post reported that scam operations had gathered more than a million dollars using Auckland ATMs, as details of more than 500 bank customers had been scanned and stolen by the scammers' skimming devices.

Westpac spokesman Chris Mirams said about 30 credit and debit card customers had so far been victimised, and all of the money had been drawn from ATMs in Canada.

But Mr Miriams and Ms Lloyd both said it was too soon to tell whether the recent Canada-linked fraudulent withdrawals suggest ATMs had been skimmed or whether another type of fraud was employed in the process.

Ms Lloyd noted the problem was not rooted on BNZ cash machine, merchant or system, and banks were coordinating in the investigation to isolate "the common point of compromise."

"All cards at risk have been secured, and customers will be contacted over the next few days to arrange replacement cards," Ms Lloyd told Fairfax NZ News.

Fairfax spoke to one victim who said he lost $1,500 over a fraudulent withdrawal during the weekend, and another ATM user, who said she lost $700 even as she had not been using her ATM card in the past two months. Both fraud victims said their money was withdrawn in Canada within the past two days.