“What has pretty much continued unabated is the use of social media, fake news, propaganda, false personas, etc. to spin us up, pit us against each other, to sow divisiveness and discord, to undermine America’s faith in democracy,” Mr. Wray said on Friday. “That is not just an election-cycle threat. It is pretty much a 365-day-a-year threat.”

In response to growing threats from Russia and other adversaries, the F.B.I. recently moved nearly 40 agents and analysts to the counterintelligence division, the senior bureau official said in an interview this month. Many of the agents will work on the Foreign Influence Task Force, a group of cyber, counterintelligence and criminal experts. Officials have made that task force, initially formed on a temporary basis before the midterm elections, permanent.

The Department of Homeland Security made its midterm election task forces permanent, folding them into an election security initiative at their National Risk Management Center. And the National Security Agency and the United States Cyber Command have also expanded and made permanent their joint task force aimed at identifying, and stopping, Russian malign influence, officials said.