The BBC tracked a huge wave of pre-election fraud allegations that continued throughout polling day and into the evening.

These included claims that the vote was “stolen” in some key states, with exaggerated versions of real events used in some cases to support these claims.

Early on Election Day in Cambria County, Pennsylvania, a Republican stronghold, problems arose with voting machines malfunctioning. The issues have been resolved and voting hours in affected areas have been extended.

However, many netizens immediately used the story to suggest nefarious activities were taking place.

A message posted at 8:45 a.m. local time on Tuesday read: “Election theft is happening!”

More rumors spread in posts that appeared throughout the day, including one around 2 p.m. that ballots in Delaware County, Pennsylvania, had been pre-marked for Kamala Harris.

In Milwaukee, the largest city in the swing state of Wisconsin, election officials made the decision to reroll about 30,000 ballots out of an “abundance of caution” after doors on the back of voting machines have been left open.

When the count was complete, it showed that support for Harris had declined compared to that for Joe Biden four years earlier.

Like many pro-Trump posters, Harris supporters pointed to real but isolated events — ballot box fires in Washington and Oregon, and a series of false bomb threats that disrupted voting at several precincts. votes on election day – as evidence of voter fraud.

However, there is no evidence that these incidents significantly changed the vote or the outcome.

Several posts from Democratic Party activists questioning the result went viral and were seen by millions of people on X and other platforms.

Pam Keith, a Harris supporter in Florida, posted: “Is it possible the machines were hacked to switch the counts from Harris to Trump? His message has been seen more than a million times on X, according to the site’s statistics. The BBC has contacted her for comment.

However, unlike Trump’s 2020 campaign, the Harris campaign and senior Democratic Party officials have not endorsed allegations of cheating or election fraud.

On Election Day, rumors of fraud also came from President-elect Trump himself, who has repeatedly claimed since the beginning of his political career that the electoral system was unfairly biased against him.

Just after 4:30 p.m., Trump posted on his social media platform Truth Social: “There’s a lot of talk about massive CHEATING in Philly. The police are arriving!!!”

The current president-elect gave no details and Philadelphia police told BBC Verify they did not know what Trump was referring to.

Republican Philadelphia City Commissioner Seth Bluestein posted on X: “There is absolutely no truth to this allegation. This is yet another example of misinformation. Voting in Philadelphia was safe .”

Trump has not repeated his allegations of fraud since Election Day.

We contacted several extremely influential accounts that regularly posted allegations of voter fraud in the run-up to the vote, but none of them responded.

With data company NodeXL, the BBC tracked accounts that interacted with Donald Trump, Donald Trump Jr, Eric Trump, Lara Trump and Elon Musk on Day X of Election Day.

Posts mentioning voter fraud peaked at 3:00 p.m. EST on November 5, but then declined significantly that evening and the next day as polls closed and results came in. .