>>Million-dollar missiles: When Syrian warheads fly, Israel doesn’t take chances | Analysis

Israel has used its David's Sling missile-defense system for the first time in battle, firing at two Syrian surface-to-surface missiles Monday morning, the military said.

An initial army investigation found that the system identified the two Russian-made SS-21 missiles, calculating that they were likely to land south of Lake Kinneret. An Israeli lieutenant colonel made the decision to use the system.

Open gallery view A trail of smoke seen in northern Israel.

>> Israel’s new missile defense system is a clear message to Iran, but it isn’t perfect | Analysis

The investigators found that one of the missiles changed course in flight and was expected to fall in Syria. One interceptor missile was therefore ordered to self-destruct. Israel also launched an interceptor missile at the second Syrian rocket, but it is unclear if it hit its target.

Earlier Monday, residents of northern Israel reported that they heard anti-aircraft batteries going off and saw a trail of smoke in the sky, shortly after sirens went off in the city of Safed and in areas near Mount Hermon in the Golan Heights. Later, more sirens sounded in the Golan city of Katzrin and nearby.

A David's Sling interceptor missile costs around $1 million. The military insists that when launching defensive missiles it does not take into account the cost.

David's Sling, also known as Magic Wand, was declared operational last year. It was developed by Israeli state-owned Rafael Advanced Defense Systems in cooperation with U.S. defense contractor Raytheon. It is an additional layer of defense against short- and medium-range missiles and rockets, in addition to the Iron Dome, Patriot and Arrow systems. It can also intercept drones.

Over the past month Israel twice shot Patriot missiles at a drone approaching from Syria, the first on June 24, when an Assad-regime commander said the drone was on a mission in southern Syria.

On July 13, Israel shot a Patriot missile at a drone entering the buffer zone between Israel and Syria; the Israeli military said the aircraft was probably shot down.

In recent days the Syrian regime has retaken the Syrian side of the Golan Heights, with a large part of the local rebel militias surrendering.

Aided by the Russian air force, the Assad regime is now focusing on the Israel-Jordan-Syria border area in the southern Golan, where the regime seeks to defeat some 1,000 fighters of a local Islamic State branch.