The U.S. was not given any warning before air strikes in Syria against what Western and Israeli officials say were weapons headed for Hezbollah militants, Reuters reports. An intelligence official said Sunday that the U.S. was essentially told of the air raids "after the fact" and was notified as the bombs went off. Israeli jets bombed Syria on Sunday for the second time in 48 hours; while Israel does not confirm such missions explicitly, an Israeli official acknowledged that the strikes were carried out by its forces. "It would not be unusual for them to take aggressive steps when there was some chance that some sophisticated weapons system would fall into the hands of people like Hezbollah," the U.S. intelligence official said. While the air raids raised fears that America's main ally in the Middle East could be sucked into the Syrian conflict, Israel typically does not feel it has to ask for a green light from Washington for such attacks, and officials have indicated in the past that Israel sees a need only to inform the United States once such a mission is under way. U.S. president Barack Obama said Saturday that Israel has the right to guard against the transfer of advanced weapons to Hezbollah, an ally of both Syria and Iran.