In 1999, a desperate Hungary reached out to the FBI for assistance in getting rid of Semion Mogilevich after European neighbors refused to help. The mafia boss had taken over the streets of Budapest, and his men had infiltrated the Hungarian Police. On April 1, 2000, the American-Hungarian task force launched its operation, and Mogilevich fled Budapest to Moscow almost immediately.

At this time, the Mogilevich organization had taken over street-level racketeering in Budapest. Russian women were illegally imported for prostitution. Black-leather-clad gangsters committed brazen extortions and other acts of violence against local citizens and visitors, including United States military personnel en route to peace keeping duties in the Balkans.

The task force began operations on April 1, 2000 and its presence was felt immediately. The Ukranian-born Mogilevich fled Budapest for Moscow and later obtained Russian citizenship

United States Attorneys’ Bulletin, International Organized Crime, September 2003

Source

https://www.justice.gov/sites/default/files/usao/legacy/2006/02/14/usab5105.pdf