Facebook acknowledged that the Federal Trade Commission opened an antitrust investigation into the company last month, a disclosure that comes on the same day the social networking giant was slapped with a record $5 billion fine from the agency.

"The online technology industry and our company have received increased regulatory scrutiny in the past quarter," the company said in an earnings release Wednesday. "In June 2019, we were informed by the FTC that it had opened an antitrust investigation of our company."

The company disclosed no other details.

On Tuesday, the Justice Department revealed its own antitrust investigation into dominant online platforms, such as Facebook, Google and Amazon. The pair of investigations are the latest indication that the rising tide of criticism in Washington against Silicon Valley shows no signs of ebbing.

Facebook agreed to pay $5 billion and reform some of its privacy practices as part of a settlement reached with the FTC earlier Wednesday. That penalty is the result of a 15-month investigation that emerged after Facebook users had their data improperly leaked to now-defunct political consulting firm Cambridge Analytica.

The FTC launched a tech task force earlier this year to examine possible anti-competitive behavior in the tech industry. It was revealed in May that the Justice Department and FTC were splitting up jurisdiction of the nation's biggest tech companies, with the FTC seeming to take the lead on Facebook.

