With the U.S. Senate and House intelligence committees looking at Russian interference in the 2016 U.S. presidential election, counsel for tech giants Facebook Inc., Google Inc. and Twitter Inc. are scheduled to testify in Nov. 1 hearings, according to spokespeople from the companies.

The probes come behind allegations that Russia used social networking sites in an attempt to interfere with the latest U.S. presidential election.

For Facebook, general counsel Colin Stretch will testify before both congressional committees, according to a company spokesperson. Facebook revealed last month that around 3,000 ads were connected to user accounts in Russia. While these ads, for the most part, did not specifically mention the election or a particular candidate, they “appeared to focus on amplifying divisive social and political messages across the ideological spectrum.”

News of Stretch's plans to testify comes just weeks after the Facebook general counsel wrote about the “difficult decision” to hand over Russian-related ads to Congress. “Disclosing content is not something we do lightly under any circumstances,” Stretch wrote in the Sept. 21 post on the company's website. He added, however, that “the public deserves a full accounting of what happened in the 2016 election, and we've concluded that sharing the ads we've discovered, in a manner that is consistent with our obligations to protect user information, can help.”

Google and Twitter execs are also planning to testify before the congressional committees. The latter, which has identified hundreds of accounts believed to be tied to Russia, plans to send acting general counsel Sean Edgett to represent the company at the Nov. 1 hearings, according to a Twitter spokesperson.

Meanwhile, Russian agents appear to have purchased search and display ads on Google “in a bid to spread disinformation during the 2016 U.S. presidential election,” Recode reported earlier this month. According to a Google spokesperson, senior vice president and general counsel Kent Walker will represent the company in Washington, D.C.

Jennifer Williams-Alvarez is based in New York and covers corporate law departments.