Washington (AFP) – Hillary Clinton issued a stern warning Thursday against the proliferation of fake news, branding it an epidemic with “real world consequences” that must be addressed in order to protect the nation’s democracy.

The Democrat Clinton lost last month’s presidential election to Republican Donald Trump in a shock upset, with several Trump critics arguing that the prominence of fake articles shared on Facebook and other social media may have affected the outcome.

The phenomenon nearly turned deadly this week when a rifle-wielding man entered a pizza restaurant in Washington saying he wanted to investigate a fake news story that wrongly stated the Comet Ping Pong restaurant was a center for child abduction linked to Clinton and a top advisor.

“It’s now clear that so-called fake news can have real world consequences,” Clinton told current and former US lawmakers on Capitol Hill where she attended a ceremony for outgoing Democratic Senate minority leader Harry Reid.

“This isn’t about politics, or partisanship. Lives are at risk,” she said as she blasted “the epidemic of malicious fake news and false propaganda that flooded social media over the past year.”

The “danger” must be addressed quickly, she stressed. “It’s imperative that leaders from the private sector and the public sector step up to protect our democracy and innocent lives.”

Clinton’s remarks were part of her second public address since her concession speech the day after the election.

“This is not exactly the speech to the Capitol I hoped to be giving after the election,” she quipped to an audience that gave her a standing ovation as she took the stage.

“But after a few weeks of taking selfies in the woods, I thought it would be a good idea to come out.”

Afterward Clinton ignored reporters’ questions about whether fake news stories had cost her the election.

The “pizzagate” story that Clinton referred to was widely shared before the November 8 vote.

No one was injured when 28-year-old Edgar Maddison Welch strode into Comet Ping Pong, packed with families on a Sunday afternoon, and fired off a round from his AR-15.

Police quickly arrested him, discovering two more weapons, and said he had told them he drove up from North Carolina to personally investigate the fake story.

But it raised to a new level the danger of the profusion of false news stories and rumors spread over the internet and in social media, much of it aimed at fortifying the views of various political and social groups.