WASHINGTON (Reuters) - A man charged with firing an assault rifle in a packed Washington pizzeria on Sunday told police he had read online that children were being held as sex slaves there and he wanted to rescue them, police said on Monday.

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The Comet Ping Pong restaurant for weeks had been the subject of fake news stories claiming falsely that it was the hub of a child sex ring organized by 2016 Democratic presidential candidate Hillary Clinton.

The stories were an example of a proliferation of fake news reports during the election year, often disseminated through websites purporting to be news outlets and quoting bogus sources.

Edgar Maddison Welch, 28, of Durham, North Carolina, was charged on Monday with four criminal counts, including assault with a dangerous weapon for firing his AR-15-style weapon three times while searching Comet Ping Pong for the child sex slaves that he told police he believed were being held there.

He surrendered peacefully after finding no such victims. No one was hurt in the incident.

The restaurant had faced social media threats ahead of the Nov. 8 election after fake news stories, known as “Pizzagate,” claimed that Clinton and campaign chief John Podesta were running a child sex ring out of the pizzeria.

The White House on Monday condemned the surge in similar politically motivated fake news, calling the stories “corrosive” to democracy.

“There’s no denying the corrosive effect these false reports have had on our political debate. And that’s concerning in a political context,” White House spokesman Josh Earnest told a briefing. “It’s deeply troubling that some of these false reports could lead to violence.”

It was not immediately known if Welch had a lawyer.

Welch pleaded guilty in 2013 to a misdemeanor charge of driving while impaired, a Rowan County Court clerk in North Carolina said.

Hours after Sunday’s incident, the sex ring story was boosted by Michael Flynn Jr., the son of retired Lieutenant General Michael Flynn, U.S. President-elect Donald Trump’s pick to be national security adviser.

“Until #Pizzagate proven to be false, it’ll remain a story. The left seems to forget #PodestaEmails and the many ‘coincidences’ tied to it,” Flynn tweeted, referring to the leak of emails tied to Podesta during the campaign.

The elder Flynn tweeted the false story a few days before the election as well.