ballot-counting process. i have a lot of confidence in the security and cyber security around the process run by state and local election officials. >> reporter: here at the department of homeland security cyber command center, they're now monitoring multiple threats. there's growing concern that more hacked documents and e-mails targeting campaigns could be released in the coming days. including potentially documents faked or altered by russia. the u.s. has also detected the probing of state voter registration systems, at least one of which has been linked to russia, though they have yet to see those systems tampered with. the department of homeland security is now coordinating efforts with all 50 states to prevent hacks scanning computer systems to identify vulnerabilitie vulnerabilities. however, cyber experts and u.s. officials make clear that changing the election results is minuscule. >> these machines are mostly offline. there's paper ballots that can be checked in most of these