A 50-year-old Alexandria man pleaded guilty Thursday in federal court in Greenbelt to participating in a scheme that distributed more than 17 million black-market cigarettes.

Jose Moreno pleaded guilty to one count of extortion conspiracy involving the transport and distribution of untaxed cigarettes, federal prosecutors said. The maximum penalty for the offense is 20 years in prison and a $250,000 fine.

Moreno is the second man to admit guilt in the scheme, which was disclosed by authorities last November, after then-Prince George’s County Executive Jack B. Johnson (D) and his wife Leslie, who days earlier had won a seat on the county council, were arrested in a sweeping corruption case. On Tuesday, Jack Johnson pleaded guilty to extortion and evidence and witness tampering. Leslie Johnson was scheduled to plead guilty to witness and evidence tampering earlier this month at a hearing that was canceled two days before it was to occur.

In April, Chun Chen, 34, of Bowie, admitted he was part of the cigarette smuggling scheme.

Officials said they learned of the cigarette smuggling ring, which prosecutors said cost the government more than $2.6 million in taxes, while investigating political corruption.

A county police sergeant, Richard J. Delabrer, 45, is also charged in connection with the cigarette scheme.