Speaking at a Washington Post event, Sanders specifically singled out Facebook as having "incredible power over the economy, over the political life of this country in a very dangerous sense."
He also stated that Amazon is "moving very rapidly to be a monopoly."
Sanders' comments come at a perilous time for Silicon Valley, which is facing increased scrutiny from lawmakers on Capitol Hill and the prospect of being broken up or subjected to stringent new regulations.
In recent weeks, Facebook's cryptocurrency Libra came under fire from lawmakers, the Federal Reserve and the Trump administration, while Republicans accused Google of being biased. The FTC has reportedly come to a settlement with Facebook, the details of which have not been made public, that includes a $5 billion fine.
"And it’s not just Amazon," Sanders said, according to Politico. "I think we need vigorous antitrust legislation in this country because you are seeing – you name the area, whether it's pharmaceuticals, whether it is Wall Street, whether it is high tech – fewer and fewer gigantic corporations owning those sectors.” He would appoint an attorney general "who would break up these huge corporations,” he added.
Sen. Elizabeth Warren, D-Mass.,who is battling Sanders and almost two dozen other candidates for the Democratic 2020 presidential nomination, called for the breakup of Amazon, Google and Facebook back in March.