Updated

Federal authorities are investigating New York City Mayor Eric Adams' use of a private email addresses and how records from seven trips he made to China have disappeared.

The New York Post, citing a source close to the probe, said the prominent NYC mayor used three private email addresses to arrange his dealings in China on his seven trips to the foreign country.

At least one of the trips, per the outlet, was partly funded by the Chinese Communist Party.

The private email accounts cannot be traced on New York City government servers, meaning that key details, such as who paid for the trips and with whom he met, remain concealed.

FBI AGENTS SPOTTED RAIDING HOME OF TOP AIDE TO NYC MAYOR ERIC ADAMS

eric adams

NYC Mayor Eric Adams (AP Photo/Peter K. Afriyie/File)

The outlet said Adams and one of his top aides and director of Asian Affairs since he took office in 2022, Winnie Greco, used the nonofficial emails between 2014 and 2021, when he was Brooklyn Borough president.

It was immediately unclear what the federal government is seeking to find from Adams’ China trips, the Post said.

The FBI declined to comment on the investigation.

Winnie Greco speaks at a reception celebrating the Mid-Autumn Moon Festival

Winnie Greco (Benny Polatseck/Mayoral Photography Office)

In a statement to Fox News, a spokesperson for Mayor Adams' office called for a "more diligent search" by authorities in regard to allegations of missing documentation.

FBI PROBES IF NYC MAYOR ERIC ADAMS RECEIVED UPGRADED TURKISH AIRLINES TICKETS IN EXCHANGE FOR FAVORS: REPORT

"Our general counsel just sent a letter to the Brooklyn Borough President Office‘s general counsel asking them to correct the record because they misstated there were no available records and to conduct a more diligent search because it obviously wasn’t done here," they said.

FBI agents

FBI agents are seen leaving the Bronx home of Winnie Greco. (FNTV)

The probe into Adam's China trips came after the FBI raided Greco's home in the Bronx in February.

The city’s Department of Investigation opened an inquiry into Greco last November after a report from The City, a local news site, that raised questions about her political fundraising and whether she used her position in the administration to obtain personal benefits, including free housework from a city employee.

WATCH:

Last year, federal investigators quietly seized the mayor's cellphones and an iPad as he was leaving an event in Manhattan.

The initial probe is believed to be focused, at least in part, on whether the Adams campaign conspired with the Turkish government to receive illegal campaign contributions from foreign sources, funneled through straw donors, according to a warrant reported on by the New York Times.

Eric Adams in January 2023

NYC Mayor Eric Adams (Lev Radin/Pacific Press/LightRocket via Getty Images)

Adams previously deflected questions about the investigation into his alleged conspiracy with the Turkish government, noting that he had not been officially accused of wrongdoing.

CLICK TO GET THE FOX NEWS APP

"Our administration will always follow the law, and we always expect all our employees to adhere to the strictest ethical guidelines," a spokesperson for the mayor previously told Fox News Digital in a statement from February. "As we have repeatedly said, we don't comment on matters that are under review, but will fully cooperate with any review underway."