Israel was behind the assassination Saturday of Syrian rocket scientist Aziz Azbar, according to a senior official from a Middle Eastern Eastern intelligence agency quoted in The New York Times on Monday.

Azbar, who headed the Scientific Research and Studies Center in Maysaf, in northwestern Syria, was killed along with ‎his driver on Saturday night when a bomb attached to ‎their car exploded.‎ As well as working at the center, which has long been associated with the development of sophisticated weaponry including Iranian Fateh missiles, Azbar was also believed to be in charge of coordinating between Iranian proxy Hezbollah and the Syrian regime and was reportedly in contact with North Korea and Russia.

The New York Times report quoted an unidentified senior official from a Middle Eastern intelligence agency as saying that Azbar’s killing was “the fourth assassination mission by Israel in three years against an enemy weapons engineer on foreign soil.”

The official also said, “The Mossad had been tracking Mr. Azbar for a long time.”

The report said Israeli leaders believed Azbar was in charge of a “secret unit known as Sector 4” at the SSRC.

It said intelligence agencies believed Azbar had “free access to the presidential palace in Damascus and had been collaborating with Maj. Gen. Qassem Suleimani, commander of Iran’s Quds Force, and other Iranians to begin production of precision-guided missiles in Syria by retrofitting heavy Syrian SM600 Tishreen rockets.”

The report quoted an “official from the Syria-Iran alliance” as saying that Azbar was in Israel’s crosshairs even before the Syrian civil war broke out in 2011 because of his involvement in the Syrian missile program.

On Monday, the pro-government Syrian paper Al-Watan also said Israel’s Mossad was behind the assassination because the modus operandi – a car bomb – was associated with the spy agency.

Israel has declined to comment on the assassination, in keeping with its policy of not commenting on such incidents.

Defense Minister Avigdor Lieberman told the Israeli outlet Hadashot Monday that he was not surprised that Syria was blaming Israel.

“Whenever something happens, they blame us. There are hundreds of explosions taking place every day in the Middle East, as well as other forms of score-settling. So we don’t take it too seriously,” he said.