The money, more than $13 million, was meant to feed seniors and other vulnerable residents of Orange County, Calif., including the growing population of older Vietnamese Americans scraping by on fixed incomes.

But the leaders of the Viet America Society, a nonprofit, have been accused of using federal pandemic aid to buy expensive homes and fund their own lifestyles instead of delivering meals.

The allegations have ensnared Andrew Do, a longtime member of the Orange County Board of Supervisors who now faces calls to resign and is expected to lose his committee assignments at a meeting on Tuesday.

Officials say that Mr. Do, a Republican who is one of the most influential Vietnamese American politicians in the country, steered lucrative pandemic-related contracts to organizations run by his daughter and his political allies that were ill-suited to feed seniors in Orange County.

F.B.I. agents last month searched at least four properties tied to Mr. Do or the Viet America Society, federal law enforcement officials have confirmed. And Orange County’s government has sued the Viet America Society to try to recoup the millions of dollars that was intended to help vulnerable residents. Charges have not been filed related to the investigation.

Mr. Do did not respond to calls for comment and his spokesman, Chris Wangsaporn, declined to comment on behalf of his office. A lawyer for Viet America Society, Mark Rosen, has insisted that the organization had provided the necessary services and was being unfairly targeted.