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

Election officials quickly rejected some accusations of voter fraud and clarified some legitimate issues that were taken out of context.

BBC Verify tracks and investigates the most widely shared claims – here are four.

1) Viral claim about ballot marking

An image on social media shows a person holding an absentee ballot that already had a mark next to Kamala Harris’ name.

The person who posted it on X claims that voting for someone else would make the vote invalid.

One post, viewed more than 3 million times, said the photo showed “strange election shenanigans in progress.”

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

He said he has sent out 130,000 ballots so far and is not aware of any complaints about mail-in ballots having pre-printed notes in candidate selection boxes .

“As no one presented a pre-marked ballot to election administrators or law enforcement, the claim that at least one ballot may have had a pre-printed mark in Kentucky does not exist currently only in the vacuum of social media,” he said.

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

2) Complaint about mail-in ballots for the military

An article on X who claims “Pentagon Wouldn’t Send Mail-In Ballots to Active Military Before Election” has been viewed more than 28 million times.

He refers to a letter addressed to Secretary of Defense Lloyd Austin, written by three Republican members of Congressexpressing “grave concern” about “deficiencies” in voting procedures for military personnel abroad.

However, the letter does not accuse the Pentagon of failing to send them mail-in ballots.

It is not the role of the Pentagon to do this: military personnel can vote abroad via the Federal Voting Assistance Program (FVAP) and the ballots are sent to them by election officials where they are recorded in the United States.

If the ballot may not arrive before the voting deadline, staff can vote via what is called a Federal Mail-in Ballot (FWAB).

The letter claims that an unspecified number of “military personnel” had requested an FWAB but were informed that their base was depleted. However, it is possible to download one and sign one via the FVAP website.

We asked the Ministry of Defense for details on the number of people affected by the problem, but they declined to comment. It said it had trained 3,000 voting support workers to help staff vote.

3) Allegation regarding “illegal voters” in Pennsylvania

Officials in the US state of Pennsylvania have rejected allegations that “illegal voters” may have requested ballots and voted at an election office in Allegheny County.

They released a statement after posts about X went viralpurporting to show “illegal voters” being guided past American voters waiting in line.

Allegheny County officials told the BBC the group was there to request an absentee ballot. He also reaffirmed that only American 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 repeatedly trying and failing to vote for Donald Trump on a voting machine in Laurel County, Kentucky – before a vote appeared next to Kamala Harris’ name – has become viral.

The person who posted it said: “I hit Trump’s name 10 times and it didn’t work. I then started recording and you can see what happened…. I replaced him with Harris.

Another article, viewed nearly seven million times, presents the video with the following claim: “Voting machines in Kentucky literally change the vote from Donald Trump to Kamala Harris.” This is election interference!

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

“After several minutes of trying to recreate the scenario, it happened. This was accomplished by hitting an area between the squares. After that, we tried for several minutes to start again and were unsuccessful,” 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 that the machine is working properly.

“In an election of this magnitude, there are always going to be problems,” said Joseph Greaney, a voting expert at the US election site Ballotpedia.

“It may be one or two machines, but people extrapolate these issues to larger issues, but I would say with a good degree of confidence that these are isolated incidents and they are detected “, he added.

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