Hillary Clinton returned to Capitol Hill for the first time since the presidential election and gave a warning about the spread of fake news.

“The epidemic of malicious fake news and false propaganda that flooded social media over the past year — it’s now clear that so-called fake news can have real-world consequences,” Clinton said at a ceremony honoring Senate Minority Leader Harry Reid (D-Nevada), who is leaving Congress.

“This isn’t about partisanship or politics,” Clinton added. “Lives are at risk. Lives of ordinary people, just trying to go about the day, do their jobs, contribute to their communities. It is a danger that must be addressed, and addressed quickly. Bipartisan legislation is making its way through Congress to boost the government’s response to foreign propaganda, and Silicon Valley is starting to grapple with the challenge and threat of fake news. It is imperative that leaders in the private sector and the public sector step up to protect our democracy and innocent lives.”

Clinton’s unsuccessful presidential campaign had to contend with the spread of fake news stories on social media, including one false report that accused her of running a child sex ring out of a Washington DC pizzeria. Last week, a man was arrested for firing an assault rifle inside the restaurant, reportedly motivated to go to the eatery after reading the fake news reports. According to NBC News’ Andrea Mitchell, Clinton spoke with the owners of the restaurant on Thursday.

The issue of fake news has gained greater attention in the wake of the election. Even Pope Francis spoke out about it, saying that the spread of false reports is “probably the greatest damage the media can do.”