Jerusalem -- Israeli jets struck a series of Iranian military targets in Syria early on Monday, the military said in a rare departure from its years-long policy of ambiguity regarding activities in neighboring war-torn Syria. The military said the targets included munition storage facilities, an intelligence site and a military training camp.

The strikes were in response to a surface-to-surface rocket that Iranian forces fired toward Israel on Sunday that was intercepted by Israel's Iron Dome missile defense system over a ski resort in the Golan Heights. That followed a rare Israeli daylight air raid near the Damascus International Airport.

The Britain-based Syrian Observatory for Human Rights said Monday's strikes lasted for nearly an hour and were the most intense Israeli attacks since May. It said 11 were killed in the strikes. The Russian military said four Syrian troops were among those killed. There were no further details on the casualties or their nationalities.

Lt. Col. Jonathan Conricus, an Israeli military spokesman, said the Iranian missile attack that prompted the strong Israeli response was "premeditated." Iranian forces in Syria fired the mid-range surface-to-surface missile toward Israel from the Damascus area -- a missile that had been smuggled into Syria specifically for that purpose, he said. Conricus declined to further identify the type of missile, but said it hadn't been used in any of the internal fighting of the civil war and had "no business" being in Syria.

Missile fire is seen over Damascus, Syria, January 21, 2019. SANA/REUTERS

Israel only recently acknowledged carrying out hundreds of strikes in Syria in recent years. It previously typically offered only general warnings against allowing Iran to establish a military foothold in Syria and refrained from commenting directly for fear of triggering a reaction and being drawn into the deadly fighting.

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Monday's announcement went a step further, reporting the strikes in real time and detailing the targets.

Conricus would not confirm whether the measures marked an official abandonment of the policy of ambiguity, merely saying that it was a "retaliatory strike against active aggression by Iran."

He said Israel had sent warnings to Syria ahead of the attack to refrain from attacking Israeli warplanes, but that Syria ignored those warnings and fired anti-aircraft missiles. He said Israel responded by destroying Syrian anti-aircraft batteries. The Russian military said that the Syrian air defenses shot down over 30 Israeli cruise missiles, a claim that was doubted in Israel.

Israel holds Syria responsible for allowing the Iranian forces to use Syrian territory as a base of operations against Israel. "Syria yesterday paid the price for allowing Iran to conduct attacks and to plan attacks from its soil," he said.

Iran "attempting to entrench itself in Syria"

The Syria war has long been a delicate balancing act. It is a battlefield where long-time regional foes have proxy forces, and in many cases their own forces, facing off in a battle not just for territory, but for influence in the heart of the Middle East.

Israel shares a (disputed, as both states claim the Israeli-occupied Golan Heights) border with Syria, where the Assad regime has been propped up in part by fighters and state forces from Iran, Israel's arch rival.

In the wake of President Donald Trump's decision to pull all 2,000 U.S. troops out of Syria, several senior U.S. military and civilian officials -- including Mr. Trump's secretary of defense and top civilian envoy to the anti-ISIS coalition -- have resigned and warned that the move will create a dangerous power vacuum in the country.

Already, through attacks like the one last week which killed four Americans in Manbij and a new bombing attack targeting a joint U.S. coalition patrol on Monday, ISIS has sought to at least show an emboldened stance.



But in addition to the defeat of ISIS, the White House has also said that the U.S. troop presence and overall mission in Syria is aimed at limiting Iran's influence in the country. Israel will have worried by Mr. Trump's sudden decision to order a withdrawal from Syria, and since his initial announcement the White House has sought to clarify that Iran's influence and physical presence in the country is still deemed unacceptable. At least a couple hundred U.S. troops in southern Syria have been ordered to remain in the country indefinitely to counter the Iranian presence there -- at Israel's request, according to The Associated Press.

Both ex-Defense Secretary Jim Mattis and former anti-ISIS coalition envoy Brett McGurk have warned that Iran, like ISIS, could be encouraged by Mr. Trump signalling an imminent U.S. departure.

On Monday, the chief of Iran's air force, Gen. Aziz Nassirzadeh, said his forces were, "impatient and ready for a fight against the Zionist regime to wipe it off the Earth," according to a news website affiliated with Iran's state television. Iranian officials have repeatedly threatened to annihilate Israel.

Speaking after the Israeli strikes on Monday, Prime Minister Benjamin Netanyahu said during an inauguration event for an airport that his country was, "acting against Iran…Those who threaten to destroy us will bear full responsibility."

"By firing towards Israeli civilians, Iran once again proved that it is attempting to entrench itself in Syria, endangering the State of Israel & regional stability," Israel's military said in a statement, vowing to "continue operating determinedly to thwart these attempts."

There has long been fear that if the nascent battle between Israel and Iran, simmering within Syria's borders now for more than seven years, erupts into a full-blown conflict, it could draw the U.S. -- Israel's closest and most valuable ally -- into much wider regional conflict.