India richest man, Gautam Adani, has launched a hostile takeover of the country’s popular NDTV television network in a deal that has sparked concerns about the future of one of the media outlets prepared to criticise Narendra Modi’s government.

In a stunning coup that blindsided the network’s high-profile founders, a unit of Adani’s sprawling conglomerate said on Tuesday that it will be acquiring a 29.18% stake in NDTV in a complex deal involving one of the network’s investors.

Under Indian takeover regulations, the move triggers an open offer for a stake of another 26%. If that is successful, Adani would be left with a controlling stake of 55%.

NDTV – which was founded in 1988 by journalists Prannoy Roy and his wife, Radhika Roy – operates national channels in English and Hindi, along with a business channel and online news websites.

But it revealed on Tuesday that it knew nothing about the takeover until Adani announced its move.

“The NDTV founders and the company would like to make it clear that this … was executed without any input from, conversation with, or consent of the NDTV founders, who, like NDTV, have been made aware of this exercise of rights only today,” it said in a statement.

One of the nation’s most popular news organisations, NDTV is regarded as one of the few media groups that takes a critical view of Modi’s BJP-led government policies. Guatam Adani is a strong ally of Modi, who has been known to fly on Adani corporate jets.

Dipti Lavya Swain, founder and managing partner at DLS Law Offices, said: “From NDTV’s statements, it seems this may not be a friendly takeover which generally is as per agreed terms and mechanism, and in fact, may end up being a hostile takeover.”

The network is also the home of India’s most respected news broadcaster and anchorman, Ravish Kumar, who is also senior executive editor of NDTV.

But one media commentator said that the takeover could see an exodus of personalities from NDTV.

“[NDTV] was unabashedly pro-Congress and anti-BJP,” said author and media entrepreneur, Minhaz Merchant. “The Adani buyout will see an exodus of anchors and the channel will move editorially from left to centre.”

The takeover will also pit Adani against his billionaire rival, Mukesh Ambani, boss of the huge Reliance Industries group, which is already an established power in the country’s media sector through a controlling interest in Network18.

In March, Adani, who has seen his wealth balloon in recent years thanks to investments in solar energy, made his first bet in the media sector by taking a minority stake in local digital business news platform Quintillion. But the proposed NDTV transaction marks Adani’s highest-profile media bet to date.

“NDTV is the most suitable broadcast and digital platform to deliver on our vision,” Adani Group executive Sanjay Pugalia said in the statement.

While Adani did not disclose financial details of the group’s planned 29.18% stake purchase, it said its subsequent open offer would be for 294 rupees ($3.68) per NDTV share, which would be worth 4.93bn rupees. That open offer price is at a 20.5% discount to NDTV’s Tuesday’s close of 369.75 rupees.