The verified Facebook pages for SpaceX and Tesla have been eliminated after Elon Musk, the chief executive of both companies, was dared by a Twitter user to delete them.

The social media site has been roiled by reports that Facebook user data was exploited by British political consultancy Cambridge Analytica on behalf of President Donald Trump's 2016 election campaign.

The official Facebook pages for Tesla and SpaceX had roughly 2.6 million followers each.

#deletefacebook

On Friday morning, Musk replied to a tweet that Brian Acton, a cofounder of WhatsApp, wrote earlier in the week. Acton, who made a fortune when Facebook bought WhatsApp for $16bn in 2014, tweeted the trending "#deletefacebook" hashtag, adding that "it is time".

"What's Facebook?" Musk joked.

A user then challenged Musk to delete the SpaceX Facebook page. Musk coyly agreed and said he did not know there was such a page. It appears he also ordered the elimination of the Tesla page as well when another Twitter user brought it to his attention.

"Delete SpaceX page on Facebook if you're the man?" a user tweeted to Tesla Chief Executive Musk. His response: "I didn't realize there was one. Will do."

The Facebook page for Tesla-owned Solar City also appears to have been removed.

Many users also urged the billionaire to delete the profiles of his companies on Facebook's photo-sharing app, Instagram.

"Instagram's probably ok ... so long as it stays fairly independent," Musk responded.

The trio of Musk-led companies all still has verified accounts on Instagram, which is owned by Facebook.

What's Facebook? — Elon Musk (@elonmusk) March 23, 2018

'D on't care'

"I don't use [Facebook] & never have, so don't think I'm some kind of martyr or my companies are taking a huge blow," Musk tweeted later. "Also, we don't advertise or pay for endorsements, so … don't care."

Musk has had run-ins with Facebook Inc founder Mark Zuckerberg in the past.

Last year, a war of words broke out between Musk and Zuckerberg over whether robots will become smart enough to kill their human creators.

When Zuckerberg was asked about Musk's views on the dangers of robots, he chided "naysayers" whose "doomsday scenarios" were "irresponsible".

Shares of Facebook tumbled another 3.3 percent Friday to close out the week at $159.39. The stock has fallen about 14 percent over the course of the week. Widely publicized reports about Cambridge Analytica's ability to misuse the data of 50 million Facebook users during the 2016 election came out over the weekend.