TEL AVIV, Israel — Israel on Sunday declared its border opposite the southern Syrian city of Quneitra in the Golan Heights a closed military zone following two straight days of attacks on regime assets in response to spillover fire from the Syrian civil war.

On Sunday, Israel attacked two artillery positions and an ammunition truck belonging to the Syrian Army. The attacks came in response to shells from ongoing battles between rebel and regime forces that crossed Syria's southern border into Israeli territory.

Following Sunday's attacks, Israel took "a precautionary measure and instructed civilians to refrain from moving and gathering in open areas adjacent to the border," according to an Israel Defense Forces (IDF) statement.

It was the second time in as many days that Israel responded to cross-border spillover from intensified exchanges between rebel forces and those loyal to the Assad regime. On Saturday, the Israel Air Force attacked three Syrian regime assets, including two tanks.

In both instances, the cross-border fire appeared to be an unintentional consequence of ongoing clashes between rebel and regime forces. Nevertheless, as has been Israel's policy since the beginning of the six-year civil war, the Israeli military responded to the source of fire breaching its border in the northern Golan Heights.

"Our policy is clear," Israeli Prime Minister Benjamin Netanyahu told Cabinet members on Sunday. "We are not willing to accept any 'drizzle' or 'spillover' fire of any type; not of mortars, not of rockets, not of shelling, on any of our fronts. We will respond with force to all forms of harm to our territory and to our citizens."

On Saturday, the IDF reiterated that Israel holds the government of Syria responsible for all fire on its territory, whether intentional or not. It released footage showing precision attacks on a heavy machine gun position and two tanks beyond its northern border.

"We have no intention to allow violations of our sovereignty and harm to our security, even if it involves errant fire between rebels and the Syrian regime," Israeli Defense Minister Avigdor Liberman said on Saturday evening after touring the area and conferring with senior commanders.

"We will respond with force, determination and good judgment in every such instance, exactly as we have done today," Liberman said.

He added, "The Assad regime, from our perspective, is responsible for what occurs in its territory, and it will continue to bear the consequences of such events."

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