The reputed head of a vast network of Armenian gangsters has pleaded guilty in New York to racketeering charges.

Armen Kazarian entered the plea in federal court in Manhattan on Friday. Kazarian was accused of being the boss of a network of criminals who used bogus health care clinics and other means to try to cheat Medicare out of $163 million.

When the FBI announced the charges in October 2010, they had said that it was the largest fraud by one criminal enterprise in the program's history.

The 47-year-old Glendale, Calif., resident could face up to 20 years in prison.

Kazarian, is alleged to be a "Vor," a term translated as "Thief-in-Law." The term "Vor" refers to a member of a select group of high-level criminals from Russia and the countries that had been part of the former Soviet Union, including Armenia. This is the first time a Vor has ever been charged and arrested for federal racketeering crimes.

Sentencing was scheduled for Oct. 6.