This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

The Justice Department is launching a formal antitrust investigation of the nation’s biggest tech companies, raising the stakes for Silicon Valley after weeks of anticipation in Washington.

The investigation appears wide-ranging and could cover conduct from numerous firms. Policymakers in Washington have increasingly focused on complaints of anti-competitive behavior concerning Amazon, Apple, Facebook and Google; while those companies were not named by the Justice Department on Tuesday, the agency indicated it will look into areas where those companies are dominant players.

“The Department’s review will consider the widespread concerns that consumers, businesses, and entrepreneurs have expressed about search, social media, and some retail services online,” the DOJ said in a press release Tuesday afternoon. “The Department’s Antitrust Division is conferring with and seeking information from the public, including industry participants who have direct insight into competition in online platforms, as well as others.”

The DOJ and the Federal Trade Commission had previously negotiated to divide up oversight jurisdiction over the tech industry, with Justice assuming responsibility for Google. But the new, broader probe is separate from a potential Google-specific investigation, according to the Wall Street Journal, which was the first to report the review.

Amazon and Apple didn’t immediately respond to requests for comment. Facebook declined to comment, and Google also declined to comment but referred CNN to testimony company executives delivered before Congress last week.

The DOJ announcement follows a week of congressional hearings that were bruising for the tech industry. Lawmakers slammed Facebook over its attempts to enter the financial services industry with a new digital currency, Libra. Amazon faced tough questions over its relationship to third-party sellers on its own platform, and Google over fake listings on Google Maps.

Rep. David Cicilline, a New Jersey Democrat who heads the House Judiciary Committee’s antitrust panel, on Tuesday sharply criticized the three companies in letters to their executives, accusing the companies of providing “evasive” testimony and demanding further answers. Ciciline is leading what he has described as a “top-to-bottom” investigation into the tech platforms.

The DOJ announcement also comes as Facebook braces for a multi-billion-dollar fine from the Federal Trade Commission that was spurred by an investigation into numerous privacy mishaps by the social media giant during and after the 2016 election.