California Democrats Sen. Dianne Feinstein and Rep. Adam Schiff are asking Twitter and Facebook to probe whether a hashtag promoting the release of a classified memo compiled by Republicans was propagated by Russian bots.

In a letter sent to the two companies’ CEOs Tuesday, Schiff and Feinstein asked the social media giants for “urgent assistance” in “our efforts to counter Russia’s continuing efforts to manipulate public opinion.”

The memo in question was authored by Rep. Devin Nunes’ (R-CA) staffers. It reportedly contains classified information about the conduct of senior Department of Justice and FBI officials that allegedly proves Republicans’ claims of the Justice Department’s bias against President Donald Trump. The memo was made available to the entire House of Representatives on Thursday, which prompted calls on social media for the memo to be made public, including a Twitter hashtag “#ReleaseTheMemo.” The memo reportedly has not been shared with the Justice Department, Politico and the Daily Beast reported.

I read the classified memo related to the DOJ, FBI, & FISA & possible Russian collusion in the 2016 elections. I was disturbed by its contents & it should be released to the public. I signed a letter, with 63 of my colleagues, to HPSIC Chairman Nunes calling to #ReleaseTheMemo pic.twitter.com/RS0O48B4Ms — US Rep Rodney Davis (@RodneyDavis) January 23, 2018

Citing reports from multiple news outlets, Schiff and Feinstein said that by Friday the hashtag “was ‘the top trending hashtag among Twitter accounts believed to be operated by Kremlin-linked groups’” and was being used “‘100 times more than any other hashtag’ by accounts linked to Russian influence campaigns,” the pair said in the letter.

They asked Facebook and Twitter to determine by Jan. 26 how many Russian influence accounts were linked to social media posts calling for the release of the memo; “the frequency and volume of their postings on this topic;” and how many non-bot Twitter and Facebook users had been exposed to posts calling for the memo’s release.

Read the letter below: