By Ramishah Maruf and Aishwarya Iyer, CNN

New York/New Delhi (CNN) — Indian billionaire Gautam Adani and other executives were indicted in New York on Wednesday by US prosecutors for their alleged roles in a yearslong, multi-million-dollar bribery and fraud scheme involving plans to develop a major solar power plant.

The Department of Justice (DOJ) said in a statement that Adani, a key ally of Indian Prime Minister Narendra Modi, and seven other executives, including his nephew Sagar Adani, promised more than $250 million in bribes to Indian government officials to secure solar energy contracts.

The impact of the allegations, which come more than a year after a US short-seller accused Adani Group of stock manipulation and accounting fraud, was immediately felt across the sprawling conglomerate. On Thursday, shares in the group’s listed firms fell between 10% and 20%, wiping out just under $30 billion in total market value according to Reuters data.

It has also created political waves inside India with the Indian National Congress, a major rival of Modi’s ruling Bharatiya Janata Party, renewing calls for a parliamentary investigation into Adani’s companies.

The DOJ alleges the solar energy supply contracts were projected to raise more than $2 billion in profits after tax over an approximately 20-year period.

Authorities say Adani, 62, personally met with an Indian government official to “advance” the scheme, which took place between 2020 to 2024. The defendants frequently met and allegedly discussed the bribery scheme, including evidence on several phones.“This indictment alleges schemes to pay over $250 million in bribes to Indian government officials, to lie to investors and banks to raise billions of dollars, and to obstruct justice,” Deputy Assistant Attorney General Lisa Miller said in the statement.Authorities say Adani, 62, personally met with an Indian government official to “advance” the scheme, which took place between 2020 to 2024. The defendants frequently met and allegedly discussed the bribery scheme, including evidence on several phones.

“These offenses were allegedly committed by senior executives and directors to obtain and finance massive state energy supply contracts through corruption and fraud at the expense of US investors,” she added.

In a statement sent to CNN, the Adani Group called the allegations “baseless and denied.”

“The Adani Group has always upheld and is steadfastly committed to maintaining the highest standards of governance, transparency and regulatory compliance across all jurisdictions of its operations. We assure our stakeholders, partners and employees that we are a law-abiding organisation, fully compliant with all laws,” said a spokesperson for the group.

Worth more than $85 billion, Adani, the founder of his eponymous group, is Asia’s second-richest person behind countryman Mukesh Ambani, according to Bloomberg’s Billionaires Index.

Canceled bond sale

In a letter to India’s two main stock exchanges, Adani Green, which is building the world’s biggest energy plant on the edge of Western India, acknowledged the separate criminal and civil indictments brought by US officials. Sagar Adani is executive director of the company.

“In light of these developments, our subsidiaries have presently decided not to proceed with the proposed USD denominated bond offerings,” it said. Reuters and the Financial Times reported the bond sale was worth $600 million.

US authorities said Adani and his associates tried to hide the alleged bribery schemes from US investors “in order to obtain financing, including to fund those solar energy supply contracts procured through bribery.”

They referred to documentation including a cell phone to extensively track specific details on the bribes, a photograph of a document summarizing various bribe amounts and PowerPoint and Excel analyses “that summarized various options for paying and concealing bribe payments.”

In a parallel civilaction, the Securities and Exchange Commission also charged both Adanis (as executives of Adani Green Energy Ltd) and Cyril Cabanes, an executive of Azure Power Global, for the bribery scheme that the SEC said allowed both companies to capitalize off a lucrative contract by the Indian government. The SEC said Adani Green raised more than $175 million from US investors on those misrepresentations.

CNN has reached out to India’s Ministry of External Affairs for comment.

For more than a year, the Adani Group has been trying to restore its reputation following allegations made in January 2023 by the US short-seller Hindenburg Research of a “brazen stock manipulation and accounting fraud scheme. The billionaire’s fortune, which at one point in 2022 was worth more than that of Jeff Bezos, plummeted over $80 billion following the report.

In its investigation, which Hindenburg said took two years to compile, the American firm had questioned the “sky-high valuations” of Adani companies and said their “substantial debt” put the entire group “on a precarious financial footing.” Short-sellers make money by betting that a company’s stock will fall.

The Adani Group published a 400-page rebuttal, calling the Hindenburg analysis “nothing but a lie.”

Adani began his career in diamond trading. He set up a commodity trading business in 1988, which later evolved into Adani Enterprises, and now has firms in key sectors ranging from ports and power to media and clean energy.