The Russian-made weapon has been a particular worry for the Pentagon because it expanded Syria’s ability to threaten Western ships that could be used to transport supplies to the Syrian opposition, enforce a shipping embargo or support a possible no-flight zone.

The missile also represented a threat to Israel’s naval forces and raised concerns that it might be provided to Hezbollah, the Lebanese militia that has joined the war on the side of the Syrian government.

The attack against the missiles came to light after Syrian rebels said that they were not responsible for large explosions at Latakia on July 5, and that a missile warehouse had been hit. American officials did not provide details on the extent of the damage or the number of missiles struck.

Israeli officials have said they would not take sides in the civil war in Syria, but they have made it clear that Israel is prepared to carry out airstrikes to prevent sophisticated weapons from being diverted to Hezbollah.