In the final weeks of the US election campaign all manner of false and misleading things are being shared on social media. Here are some of the most recent - and false - claims. Postal votes The Trump campaign has often claimed, without evidence, that increased postal voting ("mail-in" is the American term) due to the pandemic will lead to tremendous fraud. In fact, electoral fraud is incredibly rare. Last week, President Trump suggested 50,000 people in Ohio getting erroneous absentee ballots was evidence of a "rigged election". He repeated the example at a town-hall event on Thursday, when the moderator put it to him that the director of the FBI says there is no evidence of widespread fraud. The elections board in Franklin County, Ohio, said the ballot error was a "serious mistake" but in its response to the president's tweet, it added: "Our board is bipartisan and our elections are fair. And every vote will be counted." The error came through a technology malfunction - a high-speed scanner stopped working - that meant a chunk of more than 250,000 absentee ballots, for those not voting in person in their state, sent out were inaccurate. Everyone affected now has the correct voter slip, the elections boards said, and there are various safeguards in place to make sure no one votes twice. "Dumped" ballots In September, pictures of ballot envelopes in California were shared thousands of times on Facebook along with further unsubstantiated claims of "vote rigging". The official County of Sonoma Facebook page published a statement addressing the claims. "The pictures are of old empty envelopes from the November 2018 election that were disposed of as allowed by law," they said. The county's ballots for this year's presidential election had not yet been sent out to voters when the pictures were shared. Numerous national and state-level studies show that voter fraud is incredibly rare in the US. There have been isolated cases of postal-ballot fraud and the FBI is currently investigating a case of nine military ballots that were discarded in Pennsylvania. But Ellen Weintraub, commissioner of the Federal Election Commission, which oversees campaign spending laws, has said: "There's simply no basis for the conspiracy theory that voting by mail causes fraud."