The Israeli army on Sunday fired warning shots at Syria after a Syrian mortar shell landed in a military post on the Golan Heights, dpa reported.
Israeli media said it was the first time since the 1973 Middle East war that the Israeli army had fired at Syria.
It was the second time in a few days that Syrian shells landed on the Golan Heights, which Israel captured from Syria in the 1967 Middle East war and later annexed it. The two countries remain technically at war and UN peacekeepers patrols a buffer zone there.
Earlier this week bullets fired from Syria hit an Israeli military vehicle on the Golan Heights and three Syrian tanks last week strayed into the buffer zone, further highlighting the risk that the Syrian civil war could spark a wider conflict.
Turkey, which borders Syria to the north, has also been responding to Syrian shelling.
An Israeli military spokeswoman said Sunday's mortar shell caused no injuries or damage. The Israeli army said in a statement it would respond "severely" if such incidents occur again and that it had filed a complaint with the UN peacekeeping force.