Thousands of credit card users have been hit by a technical glitch that caused transactions to be duplicated.

One Kiwibank customer said almost $5000 was taken from his card after a pizza purchase made last night was duplicated 300 times.

Kiwibank said about 500 customers were affected due to an issue with one of its vendors, and it was working to fix the problem.

BNZ said 6000 of its customers had been impacted, but it had resolved the issue.

It said an external credit card service provider told it the glitch happened between 10 and 10:30pm on Friday night.

This story was originally posted on Radio New Zealand