Israeli aircraft attacked military sites on the outskirts of Damascus, Syria said, sending a fireball over the capital in what a top Syrian official said amounted to a declaration of war.
Israel didn't confirm involvement in the assault that rocked the Syrian capital. Jonathan Spyer, a political scientist at the Interdisciplinary Center in Herzliya, Israel, said the Jewish state was betting it could strike because Syrian President Bashar al-Assad is too mired in his own civil war to carry out reprisal threats.
Syria's Deputy Foreign Minister Faisal al-Mekdad told CNN the airstrikes were a "declaration of war" and that the government would retaliate in its own time. The country's information minister, Omran al-Zoubi, said in a statement on state TV that the attack opens doors to all possibilities and that Syria would use "any means" to protect its people.
Israeli Prime Minister Benjamin Netanyahu didn't address the attacks in opening remarks to his weekly Cabinet session.
Syria deployed rocket batteries directed toward Israel, the pro-government Damas Post website said, and the Israeli army said two Iron Dome missile defense batteries were deployed in the north.
Egyptian foreign minister Mohamed Kamel Amr condemned the Israeli airstrike, according to the official MENA news agency. Yemen's government also denounced the raids, the state-run Yemen News Agency reported.
United Nations Secretary General Ban Ki-moon urged all sides to "exercise maximum calm and constraint" in order "to prevent an escalation of what is already a devastating and highly dangerous conflict." The Syrian civil war has claimed more than 70,000 lives, and 1 million refugees have fled to Lebanon, Jordan, Turkey and other countries, according to UN estimates.
"Israel is taking a calculated risk that Assad, Iran and Hezbollah are right now fighting a war against the Syrian rebels and probably don't want to open up a second front against a far more formidable enemy," Spyer said by telephone.
Israel is suspected of having bombed Syria three times since the rebels started their revolt. Israel has not confirmed any of these attacks. Hezbollah and Iran are backing Assad in his war against the rebels.