In a rare public admission, Israel confirmed early Monday that it carried out airstrikes on Iranian military targets inside Syria.
"We have started striking Iranian Quds targets in Syrian territory. We warn the Syrian Armed Forces against attempting to harm Israeli forces or territory," the military tweeted.
It gave no further details.
But Israel launched the airstrikes after it intercepted a missile over the Golan Heights, hours after what Syria says were missiles fired near the Damascus airport.
Syrian state media say air defenses repelled an Israeli air raid near the international airport south of Damascus on Sunday.
Syrian state TV said the air defenses "prevented" the attack from achieving its goals. It said Israel fired six missiles on an area near Damascus International Airport, of which five were shot down and one diverted to nearby empty farmland.
Israel rarely makes any comments on military action in Syria. But Prime Minister Benjamin Netanyahu said during a visit to Chad, "We have a defined policy — to harm Iranian entrenchment in Syria and to harm anyone who tries to harm us."
Israel and Chad restored diplomatic relations after nearly 50 years as Prime Minister Benjamin Netanyahu visited the central African nation on Sunday.
The visit and official announcement marked a milestone in Netanyahu's recent policy of seeking out new allies among developing countries that have historically sided with the Palestinians at the United Nations and other international forums.
The visit comes after Chad's President Idriss Deby visited Jerusalem in November during which the leaders discussed cooperation in agriculture, counterterrorism, border protection and technology.
Israel wants to avoid getting involved in Syria's civil war. It has appealed to Russia — the Syrian government's top ally — to keep Iranian forces away from a zone near the Syrian-Israeli border.