Few doubt that Ukraine is in Russia’s cross hairs. Ahead of the election, activity has surged from Russian-linked bots and a proliferation of fake accounts impersonating the candidates, “aimed at the provoking of hostilities between Ukrainians in social networks,” Facebook in particular, said Serhii Demediuk, the chief of Ukraine’s cyber police. He said his office also had observed an uptick in requests on dark web forums for unauthorized remote access to Ukraine’s voter registry.

“The analysis of these incidents indicates that a significant number of those publications are originating from the territory of the Russian Federation,” he said.

No amount of security is 100 percent insurmountable, particularly against Russia, which has devoted enormous resources to its global disinformation efforts, said Nathaniel Gleicher, the head of cybersecurity policy at Facebook.

“The threat actors are going to continue to innovate and try to find new ways to route around security that we put in place,” he said in an interview. “But each security protocol we put in place slows down the actors, forces them to work harder and gives your team more chances to catch them.”

Far from reacting slowly to the threats facing Ukraine, he said, Facebook has been active in confronting disinformation campaigns emanating from Russia since at least April last year. That is when the company announced it had closed 135 Facebook and Instagram accounts controlled by Russia’s Internet Research Agency, which has been linked to the 2016 election tampering in the United States.