A promotional event for Facebook's new video feature descended into a shouting match on Wednesday, as reporters quizzed the social media giant's executives about its decision to allow Fox News and Infowars on the platform.

Facebook will be featuring Fox News alongside other news organizations on Watch, while right-wing conspiracy theory site Infowars has a Facebook page that is followed by nearly a million people.

The angry exchange came on the same day a poor second quarter earnings update sent Facebook shares plunging 24%, and an investor mounted a bid to topple Mark Zuckerberg as chairman, a role he controversially combines with being CEO.

Ricky Van Veen, Head of Global Creative Strategy and Fidji Simo, Director of Product at Facebook, had combative exchanges with reporters at an event to promote Facebook Watch in Beverly Hills on Wednesday

The debate at the Television Critics Association's press tour in Beverly Hills began when Facebook's head of video was asked why Facebook still hosted Infowars when it peddled conspiracy theories including calling the Sandy Hook massacre a hoax.

The reporter noted that Infowars host Alex Jones recently spread a fake story about special counsel Robert Mueller being a pedophile, telling his audience: 'They'd let Mueller rape kids in front of people, which he did.'

Fidji Simo replied that although he found Infowars 'absolutely atrocious', Facebook's approach to freedom of expression meant the company would only reduce the distribution of Infowars posts, rather than ban it completely.

A report of the event by Entertainment Weekly said Simo explained how Facebook posted flags next to some Infowars stories warning they had been fact-checked as potentially untrue and told its algorithm not to share them widely.

'What we're trying to do is make it so that, if you are saying something that is untrue, you're allowed to say it, as long as you an authentic person,' he said. 'We try to make it so that it doesn't get much distribution.'

The reporter then asked why Facebook was allowing Fox News to post videos on Watch despite what he called its 'incorrigible' record of 'proliferating misinformation'.

Fox News will be allowed to post videos on Facebook Watch, while right-wing conspiracy theory website Infowars has nearly a million followers on the platform

Most recently, Fox News host Laura Ingraham was accused of manipulating reality when he referred to child migrant detention centers on the U.S.-Mexico border as 'summer camps'.

At this point, Facebook's head of global creative strategy, Rick Van Veen, interrupted to say they had 'limited time' and that he and Simo were not responsible for the news side of the company, according to another report of the event by Deadline.

This led to shouts of 'answer the question!' and 'we'll give you time'.

'We have a range of new shows we're presenting,' Simo said.

Wednesday proved a torrid time for Facebook, with $148 billion wiped off its value in two hours and a bid to topple Mark Zuckerberg (pictured in Paris on May 24) as company chairman

'But Fox News is still on every day, including the weekends on this programming list,' a reporter said.

'So is CNN,' Simo replied, to laughter from the crowd.

'We are really trying to show a range of programming that shows a range of the political spectrum,' Simo added.

Wednesday proved a torrid time for Facebook, with $148 billion wiped off its value in two hours after a poor second quarter update which laid bare slowing user growth and the heavy cost of responding to privacy issues on the firm's business.

And on Thursday the firm's share price dipped another 20 percent on Thursday as of 13.30 ET.

Total expenses surged 50 percent year-on-year to $7.4 billion, with much of this spent on addressing concerns about its handling of personal data and monitoring what users post, reported business.

Just two hours after the update, the company was further buffeted by a bid to topple Mark Zuckerberg as chairman by shareholder Trillium Asset Management, which has $11 million in Facebook stock, reported Business Insider.

Trillium wants to breakup Zuckerberg's combined roles as chairman and CEO, citing the firm's 'mishandling' of scandals such as Cambridge Analytica and the spreading of misinformation about the Rohingya crisis in Mynamar.

Zuckerberg's critics believe appointing an independent chairman would lead to better management, while Facebook argues this would create 'uncertainty, confusion, and inefficiency'.

Despite signs of support from other investors the bid is unlikely to succeed due to Facebook's dual share structure, which gives Class B shares, of which Zuckerberg owns 75% of the total, 10 times the voting power of Class A ones.

This means the Facebook founder controls more than half of shareholder voting power.