Santos, 37, had pleaded guilty to wire fraud and identity theft for his elaborate grifting while a lawmaker representing New York.

He turned himself in Friday at the federal prison in Fairton, New Jersey, the bureau of prisons told AFP.

Despite his guilty plea, prosecutors insisted Santos’s social media showed his claims of remorse “ring hollow”, and Judge Joanna Seybert in April handed down a sentence of seven years and three months.

The downfall of the congressman from Long Island came after it was revealed he had fabricated almost his entire backstory, including his education, religion and work history.

Santos was elected to the US House of Representatives in 2022 and indicted the following year for stealing campaign donors’ identities and using their credit cards, among other charges.

Santos used the stolen funds for Botox treatments and the OnlyFans porn website, as well as luxury Italian goods and vacations to the Hamptons and Las Vegas, according to an investigation by a congressional ethics committee.

Santos’s bizarre biographical fabrications included claiming to have worked for Goldman Sachs, being Jewish and having been a college volleyball star.

He was ultimately doomed by the congressional probe that found overwhelming evidence of misconduct and accused him of seeking to “fraudulently exploit every aspect of his House candidacy”.

Santos was expelled from the House in 2023, becoming only the third person to be ejected as a US lawmaker since the Civil War, a rebuke previously reserved for traitors and convicted criminals.