JERUSALEM - Israel's army said it fired a guided missile into Syria on Sunday, destroying a military post after gunfire flew across the border and struck an Israeli vehicle.
The shooting along the frontier in the Israeli-occupied Golan Heights was one of the most serious incidents between the countries since Syria's civil war erupted two years ago. Israel has carefully watched the violence from the sidelines, but has returned fire on several occasions.
It was not immediately clear whether the Syrian troops had fired into the Golan intentionally or whether the vehicle had been hit by stray gunfire. In either case, Israel said it held Syrian President Bashar Assad's government responsible.
"The Syrian regime is responsible for every breach of sovereignty. We will not allow the Syrian army or any other groups to violate Israel's sovereignty in any way," Israeli Defence Minister Moshe Yaalon said.
Israel's military said soldiers were on routine patrol in the Golan when they were fired upon early Sunday, hours after a military vehicle driving along the frontier between the two countries was hit and lightly damaged Saturday evening. It said Israel responded early Sunday with a Tamuz guided missile.
"We were forced to act in a targeted way and to attack and destroy the post from which this (gunfire) took place," Israeli military chief Lt. Gen. Benny Gantz said Sunday. "We will continue to operate in the Golan Heights with reason and caution, but where determination and assertive and offensive action is needed, that will also take place."
Israel captured the Golan in the 1967 Mideast war and subsequently annexed the territory in a move that has not been internationally recognized.
Since Syria's civil war broke out in March 2011, errant mortar shells or machine-gun fire have landed in the Golan a number of times. Israel believes most of the cases have been accidental, but it has responded on several occasions.
Israel is worried that the embattled Assad regime may try to draw the Jewish state into the fighting in an attempt to divert attention from the civil war. Gantz has also warned that Syrian rebels, who have captured a number of villages on the Syrian side of the Golan, could turn their attention to Israel if they defeat Assad.
Sunday's violence comes days after Israel restored ties with Turkey. Relations between the countries, once close allies, had steadily deteriorated following a 2010 Israeli naval raid on a Turkish ship trying to break Israel's blockade on Gaza. Israeli commandos killed nine Turkish activists in the operation.
Israeli Prime Minister Benjamin Netanyahu said Saturday that concerns over the crisis in Syria, which borders both Israel and Turkey, led to the reconciliation.
He said Israel and Turkey would need to communicate over the worsening situation, noting fears that Syria's stockpile of chemical weapons could reach militant groups bordering the two countries.
Israel has expressed concern that Syria's chemical arsenal could fall into the hands of militants like Lebanon's Hezbollah, an Assad ally, or Islamic extremists fighting among the rebels battling Assad.
Earlier this year, the U.S. said Israel carried out an airstrike in Syria on a convoy believed to be transporting sophisticated anti-aircraft missiles to Hezbollah. Israel has all but admitted to carrying out the airstrike, but never formally confirmed it.