State attorneys general could launch an antitrust investigation into America’s largest technology companies as soon as next month, according to a report released Monday.

The Wall Street Journal reported that several attorneys general continue to move forward with an antitrust investigation of Silicon Valley, focusing on whether these companies stifle competition by using their marketplace powers. The attorneys general would likely issue civil investigative demands, which act similarly to subpoenas, to tech giants and other companies.

The report arises as President Donald Trump’s Department of Justice (DOJ) announced its antitrust review, which will focus mainly on Google and Facebook. The Journal reported in June that several attorneys general were considering a probe into antitrust concerns regarding Silicon Valley. The Federal Trade Commission (FTC) continues to investigate Facebook, including the companies’ acquisition of nascent competitors as a means to stifle potential competitors to the social media giant. The FTC continues to look into whether Facebook purchased WhatsApp or Instagram to prevent those companies from becoming competitors.

FTC Chairman Joe Simons said recently that he remains prepared to break up big tech, even reversing past mergers, as part of the regulator’s antitrust investigation into big tech.

Reports have suggested that the antitrust investigation of the attorneys general could become bipartisan as many Democrats have an interest in curtailing the power of big tech as well.

North Carolina Attorney General Josh Stein, a Democrat, said he is “participating in bipartisan conversations about this issue.” Mississippi Attorney General Jim Hood, another Democrat, said that he continues “to be concerned with the aggregation of data in the hands of a few and [I] am always watchful of any monopoly.”

Texas Attorney General Ken Paxton, a Republican, released a statement after last month’s meeting of attorneys general that the groups of attorneys discussed “the real concerns consumers across the country have with big tech companies stifling competition on the internet.”

Google, Facebook, Amazon, and Apple declined to comment regarding the Journal report. The companies have said that they operate fairly and do not engage in anticompetitive behavior.

One Google spokeswoman referred to congressional testimony by Adam Cohen, its director of economic policy, who said that the search giant has “helped reduce prices and expand choice for consumers and merchants in the U.S. and around the world.”

Matt Perault, Facebook’s director of public policy, said that the social media giant “faces intense competition for all of the products and services that we provide.”

Apple and Amazon echoed Facebook and Google’s comments, saying that their businesses compete fairly against other companies.

Louisiana Attorney General Jeff Landry, a prominent anti-big tech lawyer, said that the state attorneys general will consider “all actions,” including antitrust law, to curb the growing power held by Google, Facebook, and Amazon.

“We have seen a tremendous amount of consolidation in regard to social platforms and the tech industry over the last decade, and the result of that has become a handful of companies that have amassed a tremendous amount of data and power over the U.S. and world economy,” Landry told Breitbart News Daily host Alex Marlow in March.