Prosecutors in Brazil said Wednesday they have reinstated over-decade-old fraud charges against US Republican Congressman George Santos, who is under fire for admitting he made up large parts of his resume.

The first-term congressman from New York, whose 2022 election win helped the Republican Party secure a narrow majority in the House of Representatives, is accused in Brazil of using a stolen checkbook to buy some $700 in merchandise from a store in 2008, according to local media.

It is the latest in a mounting pile of legal woes for the 34-year-old, who also faces a criminal investigation in New York after admitting he lied about graduating from university, working at Goldman Sachs and Citigroup, and otherwise "embellishing" his resume.

"The Rio de Janeiro state prosecutor's office has requested to reopen the case," the office said in an e-mail to AFP.

The case had been archived because investigators were unable to locate Santos.

But "the accused has now been elected to Congress in the United States, meaning he has a verified address," the prosecutor's office said.

It said it had filed a petition Tuesday to reopen the case with a criminal court in Niteroi, a city outside Rio where the alleged crime occurred.

Santos was not immediately reachable for comment.

He would face up to five years in prison if convicted in Brazil, which has an extradition treaty with the United States -- though prosecutors said as a first-time offender he would be eligible for an alternative sentence, such as community service.

The son of Brazilian immigrants, Santos has ties to the South American country that are among the aspects of his life story under scrutiny.

Prosecutors said they were unable to determine whether he had Brazilian citizenship.

He has said his grandparents were European Jews who fled "Stalin's persecution" and then Hitler's Nazis to emigrate to Brazil.

But after US media investigations questioned his claim he was Jewish and found his grandparents were in fact born in Brazil, he told the New York Post: "I am Catholic. Because I learned my maternal family had a Jewish background I said I was 'Jew-ish.'"

An investigation in the New York Times meanwhile raised questions over how Santos was able to lend his campaign $700,000 after claiming on a financial filing in 2020 that he was making $55,000 a year.