The US Justice Department is investigating HSBC Holdings PLC (HBC) clients who might have failed to inform the Internal Revenue Service about accounts in India or Singapore, Bloomberg News reported on Monday, citing three unnamed people familiar with the matter.

One client got a Justice Department letter in late June saying prosecutors had “reason to believe that you had an interest in a financial account in India that was not reported to the IRS on either a tax return” or a Treasury Department report disclosing foreign accounts, the report said. It cited a copy read by a lawyer for one of the clients.

“This is a global initiative by IRS and the Department of Justice,” the report quoted Robert McKenzie — an attorney at Arnstein & Lehr in Chicago who said he spoke to two people who got letters — as saying.

“It’s clear that the IRS and the Department of Justice are intending to pursue other depositors outside of Switzerland,” Kaplan was quoted as saying.

HSBC spokeswoman Diane Bergan declined to comment, the report said. It said the letters don’t mention HSBC by name, but are all directed to people with accounts at the bank, according to lawyers who saw them.