London(CNN) Shares in some of Indian billionaire Gautam Adani’s companies soared Friday after a US private equity firm agreed to invest nearly $1.9 billion in his embattled conglomerate.

The Adani Group said Thursday that GQG Partners had bought $1.87 billion of stock in secondary market trades across four of its companies.

Shares of the group’s flagship company, Adani Enterprises, soared nearly 17% following the announcement. Shares of Adani Ports rose almost 10%, while Adani Green Energy and Adani Transmission both gained 5%.

Winning a new foreign investor will provide some much needed respite for Adani. The group shed as much as $110 billion of its market value in the days after a report by US short seller Hindenburg Research, published January 24, alleged fraud and stock manipulation.

The fallout spooked some of company’s biggest investors, leading Adani to abandon a $2.5 billion share sale last month.

The Hindenburg report, which accused the infrastructure giant of “the largest con in corporate history,” also raised concerns about its high debt loads.

Adani has strenuously denied the allegations, calling them “baseless and discredited,” and said that it is fully able to meet its debt obligations. In early February, the company said it would pay back loans worth $1.1 billion early to calm the market rout and reassure lenders.

And Australia-listed GQG Partners, which manages more than $92 billion in assets, doesn’t appear to share the concerns of other investors.

Rajiv Jain, chairman and chief investment officer at GQG Partners, said that he believed the long-term growth outlook for Adani’s companies were “substantial.”

“We are pleased to be investing in companies that will help advance India’s economy and energy infrastructure, including their energy transition over the long run,” he added.

Adani Group finance chief Jugeshinder Singh said in a statement that the deal marked “the continued confidence of global investors in the governance, management practices and the growth” of the group’s companies.

— Diksha Madhok and Julia Horowitz contributed reporting.