Just after 7 a.m. on Election Day, Trump campaign staffer Mike Roman tweeted photos of Democratic campaign posters taped outside a Pennsylvania polling station.

“Bad things are happening in Philly,” he wrote, implying the sign broke election laws forbidding campaigning within 10 feet of a polling station.

The Philadelphia district attorney’s office debunked the claim three hours later, tweeting, “What’s described in that tweet is disinformation.”

But, hours later, misleading and false information about the state had flooded the internet. It began before Election Day, according to the New York Times, and continued today, as rumors and falsehoods have been spread by confused people, right-wing influencers, and the Twitter account of the state Republican party.

“The online misinformation has been relentless,” Jane Roh, a spokesperson for the district attorney’s office, told BuzzFeed News. “Have never seen anything like this.”

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Although the rumors surrounding Pennsylvania play into President Donald Trump’s false claims about the legitimacy of the election, in reality, most of the Election Day issues had nothing to do with the rumors. In an update sent to the press just after noon, the district attorney’s office said it had received 25 complaints about the election, 21 of which had already been addressed by its Election Task Force.

“The most ‘excitement’ the Task Force has seen so far today can be attributed to bad information or misinformation being shared on social media,” the update said.

Not all the rumors are straightforwardly false. One viral video, for example, showed a poll watcher in Philadelphia being denied entry by a poll worker. According to Kevin Feeley, a spokesperson for the Philadelphia City Commissioners, the local board that oversees elections, that situation really did happen, but the video lacked key context: The poll watcher was ultimately allowed entry.

“It was an honest mistake,” Feeley told BuzzFeed News.

He and Roh said the worker was not acting from partisan motives but rather was confused because a previous version of the law required poll watchers to remain at one location, which they had to preregister for.

Nevertheless, the post blew up on social media, and hyperpartisan outlets framed the incident like a major scandal. A story on Breitbart, a right-wing news site, received over 25,000 likes, comments, and shares on Facebook, and a post from Trending Politics, a right-wing website, earned 16,000 engagements.

“In Pennsylvania we’re seeing what appear to be repeated attempts at perception hacking — where alleged instances of hyperlocal voting irregularities (many of which are normal to election season) are amplified by misinformation-sharing influencers on Facebook and Twitter to create a false voter fraud narrative that is blown completely out of proportion,” Fadi Quran, campaign director with global civic organization Avaaz, told BuzzFeed News. “The disinformation running rampant today about the electoral process threatens to undermine one of America’s most important political rights for years to come.”

The video of the poll watcher helped launch the #StopTheSteal hashtag on Twitter, in which people are sharing dubious claims of voter interference or fraud. Media intelligence company Zignal Labs found the hashtag had been mentioned over 12,800 times on Twitter by noon on Election Day.

Unverified claims of long voting lines also received tens of thousands of mentions, Zignal found. The company said its data, collected since September, showed that swing states have been the primary targets of people pushing false information.

“One of the most hotly contested states in the Electoral College, Pennsylvania sees by far the most vote-by-mail misinformation online, with more than double that of the second state on the list (Ohio),” the company found.

Other Election Day falsehoods are spreading faster than fact-checkers can verify or debunk them.

“A steady drip of posts related to a relatively small number of voting issues being amplified and pushed as if they signal much larger problems,” Claire Wardle, a cofounder of First Draft, a fact-checking site, told BuzzFeed News. “It’s doing what it is designed to do, which is to create a narrative that suggests the electoral process is flawed.”

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