Damascus shook with the sounds of explosions just before dawn, and firing by Syrian air defenses over the city was heard throughout the night. Syria’s state news agency SANA quoted a Syrian military official as saying Israeli missiles hit air defense positions, radar stations and a weapons warehouse, but claiming most incoming rockets were intercepted.

Lt. Col. Jonathan Conricus, an Israeli military spokesman, said earlier that Iran’s Al Quds force fired the rockets at several Israeli bases, though he would not say how Israel determined the Iranian involvement. The incoming attack set off air raid sirens in the  Golan Heights, which were captured from Syria in the 1967 war.

Israel “views this Iranian attack very severely,” Conricus told reporters. He said Israel had responded, but did not provide details.

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“This event is not over,” he added.

In a statement to Fox News, the IDF asked residents of the Golan Heights to remain in special “safety zones” for the time being.

Syria’s state media said Syrian air defenses had intercepted “hostile Israeli missiles” early Thursday that were fired over southwestern Damascus. Hours later, state-run Al-Ikhbariya TV broadcast a live feed of Syrian air defenses firing into the sky above the capital, and loud explosions and air defense firing were heard through the night.

Syrian activists reported Israeli airstrikes hitting targets near Damascus. One video posted online showed a large explosion and shrapnel flying in the air. Residents reported loud sounds that rocked their buildings. It was not immediately clear what was hit.

An Israeli army spokesman, Avichay Adraee, said on Twitter that Israel was “acting against Iranian targets inside Syria,” a rare admission by an Israeli official.