The Adani group stocks continued to remain under pressure on Friday, falling up to 20 per cent in morning trade, after the US-based investment research firm Hindenburg Research made damaging allegations.

Shares of Adani Total Gas plummeted 19.65 per cent, Adani Transmission tumbled 19 per cent, Adani Green Energy plunged 15.50 per cent and Adani Enterprises tanked 6.19 per cent on the BSE.

Also, Adani Ports and Special Economic Zone fell 5.31 per cent, Adani Wilmar dipped 5 per cent and Adani Power declined 4.99 per cent.

In the broader market, the 30-share BSE benchmark declined 537.91 points or 0.89 per cent to trade at 59,667.15.

The Adani Group on Thursday said it is examining legal options to take "punitive action" against Hindenburg Research for its "reckless" attempt to sabotage a mega share sale at the conglomerate's flagship firm - a statement that the US activist investor responded by saying it stands by its report that alleged "brazen" market manipulation and accounting fraud by the group.

"The maliciously mischievous, unresearched report published by Hindenburg Research on January 24, 2023, has adversely affected the Adani Group, our shareholders and investors. The volatility in Indian stock markets created by the report is of great concern and has led to unwanted anguish for Indian citizens," Adani Group's lead head Jatin Jalundhwala said in a statement.

The report and its unsubstantiated contents were designed to have a deleterious effect on the share values of Adani Group companies as Hindenburg Research, by their own admission, is positioned to benefit from a slide in Adani shares, he said.

"We are deeply disturbed by this intentional and reckless attempt by a foreign entity to mislead the investor community and the general public, undermine the goodwill and reputation of the Adani Group and its leaders, and sabotage the FPO (Follow-on Public Offering) from Adani Enterprises," he said.

"We are evaluating the relevant provisions under US and Indian laws for remedial and punitive action against Hindenburg Research." Hindenburg, a US-based investment research firm that specialises in activist short-selling, said on Wednesday that its two-year investigation revealed that Adani Group has "engaged in a brazen stock manipulation and accounting fraud scheme over the course of decades".

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