India's Adani Group has denied involvement in a money laundering and securities fraud probe that reportedly saw the freezing of more than $310 million in funds stowed in Swiss bank accounts.

US short-seller Hindenburg Research, a longtime critic of the Indian conglomerate, cited court records reported on by Swiss media outlet Gotham City in making the claim on X on Thursday night.

"Swiss authorities have frozen more than $310 million in funds across multiple Swiss bank accounts as part of a money laundering and securities forgery investigation into Adani," Hindenburg said.

The firm added that prosecutors in the case had established that an "Adani frontman" channelled funds through the British Virgin Islands, Mauritius and Bermuda -- nations known as popular intermediaries for opaque financial transactions -- to invest in Adani stocks.

Adani Group quickly rejected the allegations, calling them "preposterous" and "baseless".

"The Swiss court has neither mentioned our group companies, nor have we received any requests for clarification or information from any such authority or regulatory body," it said in a statement.

The back-and-forth is the latest in a long-running battle between Hindenburg and the family-run Indian industrial behemoth, which has interests ranging from mining and power generation to ports and media.

Adani Group saw billions of dollars wiped from its market value last year after a bombshell report by Hindenburg accused it of "brazen" corporate fraud.

Billionaire founder Gautam Adani, Asia's second-richest man, denied the allegations made in that report, calling it a "deliberate attempt" to damage its image for the benefit of Hindenburg and other short-sellers.

Shares in Adani were flat on Friday.