The Treasury Department order bars any Americans from dealing with the militants and freezes any money they may have in the U.S. Treasury Undersecretary David Cohen predicted other financial institutions across the world, including in Lebanon, could follow suit.
Cohen, who oversees terrorism and financial intelligence issues, described the four as either high-ranking Hezbollah operatives or those directly tasked with carrying out operations. Newly-declassified details about their missions show Hezbollah's reach across much of the Sunni-dominated Mideast and into Africa and Europe, Cohen said.
"Hezbollah is determined to spread instability, plan terrorist attacks and operate well beyond Lebanon's boundaries," Cohen told reporters Thursday. "And we have seen the violence and misery that comes along with Hezbollah's influence, particularly in places like Syria and Iraq."
The Treasury Department previously has imposed sanctions on Hezbollah, as recently as last month. Hezbollah was first put on the State Department's list of foreign terror organizations in 1997.
With Iran's help, Hezbollah fighters and money have been a vital source of support to Syrian President Bashar Assad as he battles Sunni rebels in Syria's civil war.
Syria's unrest also has exacerbated simmering sectarian tensions in neighboring Iraq, where Hezbollah's influence began seeping into the country after the 2003 fall of Saddam Hussein and in the years of strife that followed.
Two of the militants sanctioned Thursday have together seeded Hezbollah's influence in nearly every Mideast country for more than two decades.
Treasury officials said Khalil Harb, a senior Hezbollah commander, has overseen militant operations since 1988, starting in southern Lebanon and working his way up to directing plots in Israel, Jordan, Cyprus, Turkey, Syria, Egypt and Yemen. He also has served as Hezbollah's military liaison between Iran and Palestinian-based groups, officials said.
In Iraq, Mohammed Kawtharani has headed Hezbollah's outreach—both in giving training, funding and other aid to local Shiite militants, and also in providing political advice. Treasury officials said Kawtharani last year helped free senior Hezbollah militant Ali Mussa Daqduq, who is considered a top threat to Americans in the Mideast and was held since 2007 for deadly attacks on the U.S. military in the holy Shiite city of Karbala. Iraqi courts in the nation's Shiite-led government last year dropped the charges against Daqduq.
Treasury officials refused to describe how Kawtharani helped secure Daqduq's release. Officials said Kawtharani has worked over the past year to send fighters to Syria to support Assad's regime.
The sanctions also were imposed on two militants—Mohammed Yusuf Ahmad Mansour and Mohammed Qabalan—accused of plotting to attack Israeli tourists in Egypt in 2008. Mansour was arrested in 2009 and sentenced to an Egyptian prison but escaped in 2011. Qabalan, who headed Hezbollah's cell in Egypt, was sentenced in absentia. Officials said he was believed to still be working in the Middle East in 2011.
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