Reserve Bank of India (RBI) data, which a Reuters reporter obtained through a right-to-information request, shows state-run banks have reported 8,670 “loan fraud” cases totalling Rs. 612.6 billion ($9.58 billion) over the last five financial years up to March 31, 2017.

Loan frauds typically refer to cases where the borrower intentionally tries to deceive the lending bank and does not repay the loan.

The figures expose the magnitude of the problem in a banking sector already under pressure after years of poor lending practices. Bad loans surged to a record peak of nearly $149 billion last year.

Bank loan frauds have steadily increased as well, reaching Rs. 176.34 billion in the latest financial year from Rs. 63.57 billion in 2012-13, according to the data, which doesn’t include the PNB case.

One of the leading legal experts expressed that “This might be the tip of the iceberg or the middle, and that is the worry,” and “The fact is we don’t know what else is out there.”

The Reserve Bank of India,  in its Financial Stability Report, called frauds in banks and financial institutions “one of the emerging risks to the financial sector”.

“In a number of large value frauds, serious gaps in credit underwriting standards were evident,” the RBI said, adding that some of the gaps include lack of continuous monitoring of cash flows and cash profits, diversion of funds, double financing and general credit governance issues in banks.

The RBI has been commended for forcing Indian banks to fully disclose its bad loans, speed up their recovery, and stop hiding fraud cases as non-performing assets.

Yet to some critics, the RBI has, at the same time, been too guarded about publicly sharing data on loan defaults or fraudulent loans. This is partly due to legal constraints on disclosing individual cases and worries investors would pummel the affected banks, making loan recovery even harder.

India’s biggest lender, State Bank of India reported 1,069 loan fraud cases in the last five financial years but did not disclose the amount.

The magnitude of the bad debt in India forced the government last year to bail out the sector by pledging to inject $32 billion over this financial year and next.

Yet analysts and credit rating agencies have long warned that solving the bad debt at India’s banking sector needs to also involve wholesale reforms of the lending practices that led to the surge in bad loans.