(Reuters) - Citigroup ( C/PN ) nearly transferred about $6 billion to a customer's account in its wealth-management business by accident, Bloomberg News reported on Monday, citing people familiar with the matter.

The near-error occurred after a staffer handling the transfer copied and pasted the account number into a field for the dollar figure, which was detected on the next business day, the report added.

Citigroup ( C/PN ) did not immediately respond to a Reuters request for comment.

The wealth division's error was reported to regulators and the company has since set up a tool to help vet large, anomalous payments and transfers, according to the report.