DHS chief: America facing 'pandemic' of cyber threats from Russia and elsewhere

Homeland Security chief Kirstjen Nielsen on Wednesday said Americans are now facing a "pandemic" of threats from cyber-spies and cyber-thieves around the world, echoing a warning she has made before.

The "viral spread" of malicious software has created "a worldwide outbreak of cyberattacks and cyber vulnerabilities," she said in her opening remarks before a Senate panel, vowing that her department is doing everything it can to protect the upcoming midterm elections from foreign interference.

"With weeks to go until the midterms, top of mind for most Americans is the Russian interference in our 2016 elections. This was a direct attack on our democracy," she said. "We should not, cannot, and will not tolerate such attacks, nor let them happen again."

By Election Day, DHS will have deployed "security sensors" to state systems around the country, covering 90 percent of registered voters, according to Nielsen.

"And on Election Day, we will be out in full force and hosting a virtual, nationwide 'situation room' to assist our partners," she said.