Mark Zuckerberg
Mark Zuckerberg, founder of Facebook.Reuters

Facebook's Mark Zuckerberg just became $5 billion poorer in a matter of hours after shares of the world's largest social network plunged amidst reports of alleged data breaches.

Investors in tech stocks were in a selling frenzy on Monday after news emerged over the weekend that U.S. President Donald Trump-affiliated data firm, Cambridge Analytica, had harvested private information from more than 50 million Facebook profiles.

The data was reportedly used for political purposes during the 2016 U.S. presidential election season, which culminated in Trump's arrival in the White House.

Mirroring the concerns, the California-based company's stock fell as much as 8 percent before closing down 6.8 percent on Monday, erasing nearly $40 billion of market value.

Other tech companies also joined the rout. Microsoft dropped more than 1.7 percent while Apple, the largest American company by market capitalization, sank 1.5 percent.

The news of data breach opened possibility of greater government scrutiny and potential regulation of the technology sector, which could shrink advertising businesses of the tech firms, analysts said.

Zuckerberg, who owns about 16 percent of Facebook's shares, is now worth an estimated $69.5 billion, according to Forbes' real-time rankings of the world's billionaires.

Zuckerberg is currently the seventh-richest person on the planet, down from fifth, after falling behind Zara cofounder Amancio Ortega and Carlos Slim Helu, Mexico's richest person, according to Forbes,

The world's richest man, Amazon founder and CEO Jeff Bezos, saw his wealth decrease by $2 billion on Monday as Amazon shares fell by nearly 3 percent.