Hackers with ties to the Russian government apparently scanned election computer systems in 21 states searching for vulnerabilities, a Department of Homeland Security official told a Congressional committee today.

Although the hackers were able to exploit a "small number" of networks, no vote tallying systems were affected, according to a Washington Post report on testimony by Samuel Liles, acting director of the Office of Intelligence and Analysis Cyber Division for the Department of Homeland Security. Liles testified before the Senate Intelligence Committee.

Government officials did not release information on which 21 states were targeted, nor the type of data that was taken from these systems, the Post noted.

Jeh Johnson, former Department of Homeland Security secretary, told the House Intelligence Committee in a separate hearing earlier this week that the scale and scope of Russia's involvement in the US elections were "unprecedented," according to the Post.

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