As millions of people voted in the US election, claims questioning the integrity of the vote have spread online.

Election officials have been quick to reject some allegations of election malpractices, in addition to clarifying some legitimate issues that have been taken out of context.

BBC Verify is tracking and investigating the most shared claims – here are four.

1) Viral claim about ballot marks

An image on social media shows a person holding a mail-in ballot that already had a check mark next to Kamala Harris’ name.

The person who posted it on X claims that voting for anyone else would void the ballot.

One post, viewed more than 3 million times, said the image showed “strange election shenanigans going on.”

BBC Verify spoke to the Kentucky Board of Elections, which rejected the allegation.

It said it had mailed out 130,000 ballots so far and had not been aware of any complaints about mailed ballots that had pre-printed markings in the candidate selection boxes.

“As no one has submitted a pre-marked ballot to election administrators or law enforcement, the claim that at least one ballot may have been pre-marked in Kentucky currently only exists in the void of social media,” he said.

The board of elections added that for mail-in ballots in Kentucky, if more than one candidate option is marked in ink, the ballot will still be counted if the voter circles their preferred option.

2) Complaint about absentee voting for military personnel

a publication in X that states “Pentagon Reportedly Failed to Send Absentee Ballots to Active Duty Military Members Before Election” has been viewed more than 28 million times.

References a letter addressed to Secretary of Defense Lloyd Austin, Written by three Republican members of Congressexpressing “serious concern” about “deficiencies” in the procedures for foreign military personnel to vote.

However, the letter does not accuse the Pentagon of not sending them absentee ballots.

It’s not the Pentagon’s job to do this: military personnel can vote abroad through the Federal Voting Assistance Program (FVAP) and election officials send them ballots where they are registered in the US.

If the ballot is at risk of not arriving by the voting deadline, staff can vote via what is called a Federal Write-In Absentee Ballot (FWAB).

The letter states that an unspecified number of “service members” had applied for a FWAB but were told their base had been depleted. However, it is possible to download and sign one through the FVAP website.

We asked the Department of Defense for details on how many people had been affected by the issue, but it had no comment. It said it had trained 3,000 election assistance officers to support staff in voting.

3) Claim about ‘illegal voters’ in Pennsylvania

Officials in the US state of Pennsylvania have rejected claims that “illegal voters” were able to request ballots and vote at an elections office in Allegheny County.

They issued a statement after posts on X went viralclaiming to show “illegal voters” being herded among American voters who had been waiting in line.

Allegheny County officials told the BBC that the group was there to request mail-in ballots. He also reiterated that only US citizens can register to vote.

It is illegal for non-U.S. citizens to vote in federal elections, and Studies show that cases where this happens are extremely rare.

4) Kentucky Voting Machine Complaint

A video that appears to show someone trying and repeatedly failing to vote for Donald Trump at a voting machine in Laurel County, Kentucky, before a vote appears next to Kamala Harris’ name, has gone viral.

The poster says: “I hit Trump’s name 10 times and it didn’t work. So I started recording and you can see what happened…. I changed it to Harris.”

Another post, viewed nearly seven million times, features the video with the claim: “Voting machines in Kentucky are literally changing the vote from Donald Trump to Kamala Harris. This is election interference!

Election officials confirmed that the video was authentic and that the machine malfunctioned, but said it was an isolated incident and the voter was able to cast his vote as planned.

“After several minutes of trying to recreate the scenario, it happened. This was achieved by hitting some area between the boxes. “After that we tried for several minutes to do it again and couldn’t,” the county clerk said in a statement.

The machine in question was taken out of service until it was inspected, and later that day the county clerk posted a video on Facebook showing the machine working correctly.

“In an election of this scale there will always be some problems,” said Joseph Greaney, a voting expert at US election website Ballotpedia.

“It may be one or two machines, but people are extrapolating them to larger problems, but I would say with quite confidence that they are isolated incidents and that they are detected,” he added.

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