MUMBAI, June 6 -- Private sector lender IDFC First Bank said a forensic review by KPMG found that the Rs.646 crore fraud uncovered at its Chandigarh branch earlier this year was an isolated incident involving collusion between branch employees, customer representatives and third parties.

In a stock exchange filing on Friday, the bank said the findings reaffirmed that the fraud was limited to the Chandigarh branch.

Nicknamed 'Project Ultra', the KPMG review found that the modus operandi involved collusion between the branch employees, certain employees of the customers, and certain individuals external to the bank.

To process the unauthorized transactions, potentially modified/edited authorization letters, cheques (including misuse of f...