U.S. national security adviser Jake Sullivan defended Israel's operations in Syria since the fall of President Bashar al-Assad, saying on Thursday it had a right to defend itself from risks to its security. "What Israel is doing is trying to identify potential threats, both conventional and weapons of mass destruction, that could threaten Israel, and, frankly threaten others as well," Sullivan told a press conference in Tel Aviv following a meeting with Prime Minister Benjamin Netanyahu. In the aftermath of Assad's flight from Syria, Israeli jets and missile ships hit military targets including fighter jets, helicopters, naval vessels, missile stores and weapons manufacturing sites to stop them from falling into the hands of the rebel forces that toppled Assad. Sullivan said the situation in Syria presented a range of risks "including the potential for fracture in that state". He added that power vacuums could give room for terrorist groups to grow and said the new power in Damascus could be hostile to neighbors including Israel.