The U.S. Treasury on Tuesday imposed new sanctions on several people and financial entities it believes are supporting the terrorist organization Hezbollah.

The U.S. Treasury Department said the new designations target individuals and companies that manage and enable Hezbollah’s overarching financial apparatus operating throughout Lebanon.

The administration of President Joe Biden on Thursday imposed sanctions on accountants, their firms and an arms facilitator accused of working for the Iran-back, Lebanon-based...