TEL AVIV – The Iranian drone intercepted by the Israel Air Force on Saturday is a relatively new stealth model with a design that appears to have been stolen from a U.S. drone that was shot down by Iran in 2011.

Photographs and video footage of the destroyed Iranian drone seem to indicate that it was a Saeqeh – or Thunderbolt in English – a stealth model unveiled by the Islamic Revolutionary Guards Corps in 2016 based heavily on the captured American RQ-170 Sentinel spy drone, aviation experts said.

In 2014, Iranian media said the country had successfully reverse-engineered the American UAV and two years later, the IRGC announced that it had built its own version.

Although the IDF did not confirm what kind of drone was intercepted in Israeli skies Saturday, the IAF’s second-in-command, Brig. Gen. Tomer Bar, said it was a sophisticated machine using “Western” technology.

The Iranian drone entered Israeli airspace and remained there for a minute and a half before being downed by a combat helicopter. Israel launched airstrikes on 12 Syrian and Iranian targets in Syria, including three air-defense batteries and four Iranian targets.

Bar said the response to “Syrian chutzpah” was “the biggest and most significant attack the air force has conducted against Syrian air defenses since Operation Peace for the Galilee” in 1982 during the First Lebanon War. He added that the airstrikes inflicted “significant harm to the Syrian Air Force’s defenses,” which included “anti-aircraft batteries purchased in recent deals [with the Russians].”

Netanyahu said on Sunday that Israel “dealt severe blows to the Iranian and Syrian forces.”

“We made it unequivocally clear to everyone that our rules of action have not changed one bit; we will continue to strike at every attempt to strike at us. This has been our policy and it will remain our policy,” he added.

On Saturday, Netanyahu had telephone conversations with both Secretary of State Rex Tillerson and Russian President Vladimir Putin, who have agreed that Israeli-Russian security coordination on Syria will continue.

Putin told Netanyahu to avoid “any steps which might trigger a new spiral of dangerous-for-all confrontation in the region,” the state-owned TASS news agency said.

In response, Syria downed an Israeli F-16 with an estimated two dozen missiles, injuring two pilots who ejected, one seriously and one lightly.

Bar said Israel would study the Iranian drone.

In the past few years, Israel’s largest defense companies have been working on anti-drone systems.

Elbit Systems unveiled the ReDrone in 2016, which has the ability to both intercept and corrupt rogue UAVs.

Rafael Advanced Defense Systems, the company behind the Iron Dome, announced last year it was developing what it called a Drone Dome system which detects and jams UAVs, and can also be deployed for intelligence-gathering.

However, the systems have still not been tested in the field.