A Chicago man posing as a rabbi attempted to steal £34 million by filing fraudulent tax returns using the identities of dead people and prison inmates.
Marvin Berkowitz, 64, pleaded guilty to tax fraud in a Chicago court on Friday.
He faces up to 25 years in prison when he is sentenced in June.
Berkowitz and his accomplices, who included family members, scoured online records for the names and social security numbers of the dead and of prisoners.
Using almost 3,000 identities, the ring successfully collected £3 million from the Internal Revenue Service and tax agencies across almost 30 states.
Berkowitz masterminded the fraud from Israel, where he lived from 2003.
He prepared the false returns in Israel and then forwarded them to accomplices in America, who were directed to mail them out from US post boxes.
The accomplices then forwarded the money to Berkowitz. At least
$1.5 million was sent to Berkowitz's relatives.
As part of the conspiracy, the Dept of Justice said, Berkowitz pretended to be an accountant, a rabbi and an attorney.
He was arrested in Jerusalem in 2009 and extradited to the US.
His son, David, of Hollywood, California, has already pleaded guilty.
Charges are pending against nine people, including Berkowitz's son, Yair, and against Berkowitz's son-in-law, Eric Berkowitz, both of Chicago.