US regulatory authorities are preparing to announce a new antitrust probe into Google as soon as next week, according to a new report from The Washington Post. The investigation is said to involve more than half of the nation’s state attorneys general. The Post says the Department of Justice has met with many of those state attorneys general, but it’s unclear whether it will be involved in the final lawsuit.

The news follows comments late last month from the DOJ’s antitrust chief Makan Delrahim that suggested the agency would be working closely with state lawmakers and regulatory authorities on future antitrust probes. Regardless, the investigation would mark a further escalation in the US government’s attempts to rein in Big Tech, and it signals that authorities at both the federal and state effort are working concurrently on a number of investigations into Silicon Valley companies.

“Google’s services help people every day, create more choice for consumers, and support thousands of jobs and small businesses across the country,” a Google spokesperson tells The Verge. “We continue to work constructively with regulators, including attorneys general, in answering questions about our business and the dynamic technology sector.”

Back in July, the DOJ announced a broad antitrust review of the technology industry’s biggest companies, including Amazon, Facebook, and Google, although the DOJ has yet to announce a formal investigation into any one company. Separately, the Federal Trade Commission has formally opened a new antitrust investigation into Facebook after fining the company $5 billion over privacy violations. The FTC has also started interviewing people regarding potential anticompetitive behavior from Amazon, although it’s unclear if the agency has launched a formal investigation into the e-commerce giant.