Russian fighter jets were scrambled to intercept incoming Israeli fighter jets in Syrian airspace, preventing the Israeli planes from carrying out strikes on a key airbase used by Iranian forces in Syria, according to reports in Russian and Iranian media outlets.

According to the story, which was carried by a Russian aviation blog as well as Iran’s Tasnim outlet, earlier this month, the Russian air force scrambled a number of advanced Su-35 fighter jets from Khmeimim Air Base to intercept Israeli planes which were inbound heading towards the Tiyas Military Airbase, or T-4, Syria’s largest airbase.

The Russian fighters managed to intercept the Israeli jets, according to the reports, and forced them to break off their planned attack on T-4.

Israel did not comment on the reports.

The T-4 airbase, which is used by not only Syria but also Iran’s Quds Force as well as the Russian military, has been the target of Israeli attacks in the past, including strikes in February and April 2018.

The Sukhoi Su-35 Flanker-E is the top Russian air-superiority fighter in service today, and represents the pinnacle of fourth-generation jet fighter design. It will remain so until Russia succeeds in bringing its fifth-generation PAK-FA stealth fighter into production.

Distinguished by its unrivaled maneuverability, most of the Su-35’s electronics and weapons capabilities have caught up with those of Western equivalents, like the F-15 Eagle. But while it may be a deadly adversary to F-15s, Eurofighters and Rafales, the big question mark remains how effectively it can contend with fifth-generation stealth fighters such as the F-22 and F-35.