The U.S. government announced a severe crackdown Tuesday on Daniel Kinahan, the accused head of an Irish organized crime group who has long been involved in boxing, including with one of its biggest stars, Tyson Fury.

Bounties of $5 million were offered for information leading to the arrest and convictions of Kinahan; his father, Christy; and his brother Christy Jr. The U.S. Department of the Treasury also announced financial sanctions against the Kinahans, other members of their group and a number of connected businesses, including a sports management company based in the United Arab Emirates, where U.S. officials say Kinahan now lives.

“The Kinahan Organized Crime Group smuggles deadly narcotics, including cocaine, to Europe, and is a threat to the entire licit economy through its role in international money laundering,” Brian Nelson, the under secretary for terrorism and financial intelligence at the Treasury Department, said in a statement.

Kinahan has previously been represented by the British law firm Brandsmiths in defamation cases. Adam Morallee, a partner at Brandsmiths, said in an email that he had “reached out for instructions” but had not yet heard from Kinahan. Kinahan’s lawyers in the United States did not respond to an email requesting comment on the sanctions.

At a news conference in Dublin, Greg Gatjanis, an associate director of the Treasury’s Office of Foreign Assets Control, compared the Kinahan group to the Camorra in Italy, the yakuza in Japan and Los Zetas in Mexico.

Outside Ireland, however, Daniel Kinahan, 44, is best known for his deep influence in boxing. In 2012, he founded MTK Global, a boxing and mixed martial arts company that represents top British boxers like Fury, Billy Joe Saunders and Michael Conlan.

MTK Global, which was not subject to sanctions by the U.S. government, said it cut ties with Kinahan after a shooting in 2016 at the Regency Hotel in Dublin at the weigh-in for a planned boxing match between Jamie Kavanagh and Antonio João Bento. According to reports in the Irish news media, Kinahan is believed to have been the target of the shooting, which killed a Kinahan associate.

John O’Driscoll, an assistant commissioner for the Irish national police service, said the shooting was a pivotal moment that led the police to stop thinking of the Kinahans as a “group of criminals located and engaged in crime in Dublin” and start thinking of them as “being a transnational organized crime group possessed of significant wealth.”

Even after the 2016 shooting, Kinahan’s connections to boxing have endured. In February he posed for a photograph with Fury in Dubai, and last month he posed for a photograph with Mauricio Sulaimán, the president of the World Boxing Council, a sanctioning organization in the sport. Kinahan was also involved in the ultimately failed negotiations to secure a lucrative two-fight deal between Fury and Anthony Joshua.

Athletes and sports officials were urged to cut all ties with the Kinahans by Drew Harris, the head of the national police service in Ireland.

“In terms of some individuals, prominent sporting individuals who are in some way connected with this grouping, I would say you need to look to your sport, to your fans, and think of your own reputation,” Harris said.

Harris also warned British broadcasters who have shown fights featuring Fury and other fighters associated with MTK Global to “look at their own business” and consider if they wanted to still be involved with them.

The sanctions against Kinahan and those associated with the Kinahan organized crime group, which authorities said were worth over a billion dollars, seek to cut them off from much of the world’s financial system. All of their property and money in the United States is blocked, and American citizens, as well as anybody else on U.S. soil, are almost entirely prohibited from engaging in transactions with them.