Israeli commandos raided and destroyed an Iranian-backed research facility and missile manufacturing site in Syria in late September, prior to the flash rebel offensive that ousted longtime leader Bashar al-Assad.

The Syrian defense industry’s Scientific Studies and Research Center (CERS), where Iranian scientists worked, and an Iranian-established missile facility were targeted by the IDF in a covert operation, according to a report from Hebrew-language outlet Kan News.

The IDF had been aware of sites for years, but began making plans to attack after intelligence indicated that advanced equipment was transferred from Iran to the missile manufacturing facility.