The United States imposed sanctions Friday on a yakuza crime syndicate, three of its members and an affiliate group over their alleged involvement in drug trafficking and money laundering.

Subject to sanctions are the Kobe Yamaguchi-gumi, the Yamaken-gumi, a subsidiary gang group, Kunio Inoue, leader of the Kobe Yamaguchi-gumi, as well as two other senior Kobe Yamaguchi-gumi members, the Treasury Department said in a statement.

"Today's designation is part of the Treasury Department's collective efforts to target the yakuza," said John Smith, acting director of the department's Office of Foreign Assets Control.

Yakuza groups have ties with criminal affiliates in Asia, Europe and the Americas, where they use front companies in legitimate industries, including construction, real estate and finance, to launder money and hide illicit proceeds, according to the department.

In the United States, they have been accused of drug trafficking and money laundering.

"This action reflects the Treasury's ongoing commitment to protect the U.S. and international financial systems from the malign influence of transnational criminal organizations and to expose persons who are supporting them or acting on their behalf," Smith said.

Friday's action freezes the designated individuals' and groups' assets that are in the United States or in the control of U.S. nationals. It also generally prohibits Americans from engaging in transactions with them.

The department has designated 17 individuals and seven entities affiliated with Japanese gang groups.