NEW YORK (CBS News) Facebook announced on Tuesday that it had detected a coordinated influence operation whose activities appeared to target divisive political issues ahead of the 2018 midterm elections.

The company detected the activity as part of an ongoing investigation into election interference, its representatives said, and had removed 32 pages and accounts from Facebook and Instagram as a result. Though the activity was not overtly linked to Russia, it was reminiscent of operations conducted by Russian accounts during the 2016 presidential election, Facebook said.

“We’re still in the very early stages of our investigation and don’t have all the facts — including who may be behind this,” the company said in a public post. “It’s clear that whoever set up these accounts went to much greater lengths to obscure their true identities than the Russian-based Internet Research Agency (IRA) has in the past.”

Facebook conveyed this information to staffers for senior congressional leaders and the national security agencies this morning by telephone, two people familiar with the outreach told CBS News.

The announcement comes one week after the company’s Head of Cybersecurity Policy, Nathaniel Gleicher, repeatedly sidestepped questions about the issue on a press call.

“We know that Russians and other bad actors are going to continue to try to use our platform before the midterms, probably during the midterms, after the midterms, and around other events and elections,” Gleicher said last week. “We are continually looking for that type of activity, and when we find things – which, we think, is inevitable – we’ll notify law enforcement and, where we can, the public.”

The company also saw a record-setting loss of $119 billion last Thursday, after its shares plunged almost 19 percent following a disappointing earnings announcement. It was Facebook’s first full quarter following the Cambridge Analytica privacy scandal, which raised widespread concerns about the company’s ability to protect its users’ data.

In recent weeks, officials from the FBI, DHS and Office of the Director of National Intelligence have all said Russian efforts spread disinformation continue. Director of National Intelligence Dan Coats said earlier this month that the intelligence community continues to see “aggressive attempts to manipulate social media and to spread propaganda focused on hot-button issues that are intended to exacerbate socio-political divisions.”

Lawmakers quickly seized on Facebook’s disclosure as evidence that threats to U.S. election security have not abated.

“Today’s disclosure is further evidence that the Kremlin continues to exploit platforms like Facebook to sow division and spread disinformation, and I am glad that Facebook is taking some steps to pinpoint and address this activity,” said Senator Mark Warner, vice chairman of the Senate Intelligence Committee. “I also expect Facebook, along with other platform companies, will continue to identify Russian troll activity and to work with Congress on updating our laws to better protect our democracy in the future.”

Warner issued a wide-ranging white paper with proposals for regulating social media platforms on Tuesday.

The Senate Intelligence Committee is scheduled to hold a hearing on foreign influence operations and their use of social media platforms on Wednesday. It is expected to hear from top Silicon Valley executives in September.

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