And questioning his mental health. A group named "Flag Officers 4 America" released a letter signed by 124 former military leaders.
The letter questioned the 2020 election result and President Joe Biden's physical and mental health.
One serving Navy leader told Politico the letter was "disturbing and reckless."
More than 120 retired US military leaders have signed an open letter appearing to advance a false conspiracy theory that the 2020 election was rigged and questioning President Joe Biden's mental capacity to serve.
"Without fair and honest elections that accurately reflect the 'will of the people' our Constitutional Republic is lost," said the letter released Tuesday by "Flag Officers 4 America," and signed by 124 former admirals and generals.
"The FBI and Supreme Court must act swiftly when election irregularities are surfaced and not ignore them as was done in 2020."