Answer
Imad Mughniyeh was a Lebanese Hezbollah military commander who was believed to have killed more Americans than any other person prior to the 9/11 attacks. He was responsible for the 1983 Beirut barracks bombing, which killed 241 U.S. Marines, and the 1985 TWA Flight 847 hijacking, which resulted in the death of one American passenger. Mughniyeh was killed in a car bombing in Damascus, Syria, in 2008.