Senior al-Qaeda leader Muhsin al-Fadhli was killed in a "kinetic strike" on July 8 while traveling in a vehicle near the northwestern Syrian town of Sarmada, Pentagon spokesperson Captain Jeff Davis was quoted as saying.
He was close confident of late al-Qaeda supremo Osma bin Laden. According to reports, he was among the few who knew in advance about the September 11, 2001 attacks on the US.
Fadhli was accused of plotting attacks against US and its allies. He was the leader of al-Qaeda's Khorasan Group which is a part of al-Qaeda's Syrian branch, Al-Nusra Front.
Fadhli had played crucial role in terrorist attacks that took place in October 2002, including against US Marines on Faylaka Island in Kuwait and on the French ship MV Limburg.
A reward of $7 million was posted by the US State Department for information leading to his death or detention.
Authorities in Kuwait, Saudi Arabia and the United States were looking for him for his involvement in terrorist activities.