People connected to the Russian government tried to hack election-related computer systems in 21 states. Samuel Liles, the Department of Homeland Security's acting director of the Office of Intelligence and Analysis Cyber Division, said vote-tallying mechanisms were unaffected and that the hackers appeared to be scanning for vulnerabilities - which Liles likened to walking down the street and looking at homes to see who might be inside. Liles was testifying before the Senate Intelligence Committee, which is investigating Russia's efforts to meddle in the 2016 presidential election. Officials in Arizona and Illinois had previously confirmed that hackers targeted their voter registration system. In a separate hearing ... former Department of Homeland Security secretary Jeh Johnson testified that Russia's meddling ... was unprecedented, the scale and the scope of what we saw them doing." He said the severity of Russia's efforts persuaded him to sign onto an Oct. 7 statement publicly blaming the Kremlin for what had happened. "We needed to do it, and we needed to do it well before the election to inform American voters of what we saw," Johnson said. FBI Assistant Director of Counterintelligence Bill Priestap ... said Russia for years has tried to influence U.S. elections but that the "scale" and "aggressiveness" of its efforts in 2016 made the attempts more significant.