The U.S. Treasury Department accused four Lebanese supporters of Hezbollah of working to expand the Shiite movement's influence in Gambia, Ivory Coast, Senegal and Sierra Leone.
U.S. Undersecretary for Terrorism and Financial Intelligence David Cohen said Hezbollah was working other channels as Iran, its "traditional patron," faces increasing sanctions pressure.
Hezbollah holds political office in Lebanon though its military activity in Syria and elsewhere has sparked interest in its militancy. The United States categorizes Hezbollah as a terrorist organization.
"As Hezbollah continues to use its global network of operatives and supporters to extend its malign influence beyond the borders of Lebanon, we will continue to use all tools at our disposal take action to disrupt these efforts," Cohen said in a statement Tuesday.
The Treasury Department suspects the four men -- Ali Ibrahim al-Watfa, Abbas Loutfe Fawaz, Ali Ahmad Chehade and Hicham Nmer Khanafer -- organized fundraising efforts, recruited members or represented themselves as ambassadors for "Hezbollah's Foreign Relations Department."
The Treasury Department said it also suspects Hezbollah of having ties to the illicit narcotics trade in South America.