U.S. officials asked Citigroup (>> Citigroup Inc) to provide information on accounts tied to four businesses affiliated with Hank Rhon, according to the news agency. These include two units each of Grupo Financiero Interacciones SA (>> Grupo Financiero Interacciones SA de CV) and Grupo Hermes SA, which are controlled by Hank Rhon and his family.

The Justice Department asked the bank to provide similar paperwork for a fifth firm, Banco Monex, that's not connected to Hank Rhon, Bloomberg said.

U.S. Justice Department spokesman Wyn Hornbuckle declined to comment.

Officials at Interacciones and Citigroup declined to immediately comment while those at Monex and Hermes could not be reached.

The Justice Department is examining anti-money laundering practices at Banco Nacional de Mexico, Citigroup’s Mexico unit known as Banamex, to see if any of its clients were involved in money laundering, the news agency said.

Neither Hank Rhon nor any of his companies have been accused of wrongdoing, the report said.

Mexico City-based Banco Nacional de Mexico embarrassed Citigroup last year when it lost more than $500 million on fraudulent loans to a supplier of state-run oil giant Pemex [PEMX.UL].

Bloomberg reported last month that U.S. authorities had expanded their money-laundering probe to Citigroup's Mexican unit.

(Reporting by Cyntia Barrera and Alexandra Alper in Mexico City, Lindsay Dunsmuir in Washington, and David Henry in New York; Editing by Bernadette Baum)