James Martin/CNET

Several federal agencies have joined the Department of Justice inquiry into the data scandal involving Facebook and consultancy Cambridge Analytica, The Washington Post reported on Monday.

The Securities and Exchange Commission, Federal Trade Commission and Federal Bureau of Investigation have joined in the probe, according to the Post. The DOJ probe follows Facebook's disclosures in March that Cambridge Analytica, a digital consultancy that had ties to the Trump presidential campaign, improperly accessed personal information on up to 87 million of the social network's users.

The investigation is also being broadened to focus on Facebook's statements following the scandal and whether its disclosures to both the public and its investors were "sufficiently complete and timely," according to the Post. In April, Facebook CEO Mark Zuckerberg testified at two congressional hearings over the controversy. His comments on Capitol Hill are also being scrutinized as part of the expanded probe, the newspaper said.

Facebook acknowledged the inquiry, but didn't comment on the report of an expanded probe.

"We are cooperating with officials in the US, UK and beyond," a Facebook spokesman said in a statement. "We've provided public testimony, answered questions, and pledged to continue our assistance as their work continues."

SEC and FTC representatives didn't immediately respond to requests for comment. The FBI declined to comment.

The expanded investigation underscores the intense pressure the US government has put on Facebook as it deals with accusations that it didn't do enough to prevent abuse on its platform or protect the personal information of its more than 2 billion users. The company is also still in the hot seat with lawmakers over Russian trolls who bought ads and posted misinformation and divisive content on the platform in an attempt to meddle in the 2016 election and sow discord among voters.

The involvement of additional federal agencies in the Justice Department probe expands the spotlight beyond Cambridge Analytica's use of Facebook data to the social network's reaction to the scandal. The social network said it first found out about data misuse from Cambridge Analytica in 2015, but didn't disclose it until this March, after inquiries from The New York Times and the Guardian.

After news of the scandal first broke in March, Zuckerberg and COO Sheryl Sandberg remained silent for five days, prompting the hashtag #WheresZuck to circulate on Twitter. After that, Zuckerberg went on an apology tour, giving interviews to several news outlets including CNN, the Times and Wired.

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