Several small burnt munition remains and larger parts resembling the “lid” (nose part) and cylindrical casing of a RBK-500 series cluster bomb suggest that Rastan was hit with an incendiary cluster bomb.
Our team has covered the use of RBK-500 ZAB-2,5SM incendiary cluster bombs against civilian targets in Syria and their presence at Russia’s airbase in Latakia governorate. We have mentioned that incendiary cluster munitions of this type weren’t used in the conflict before the Russian intervention, giving grounds to believe hat they were used by Russian, not Syrian aircraft.
This time, White Helmets found not only ZAB-2,5S submunitions, but also remnants of longer bomblets:
See more: https://citeam.org/new-evidence-of-russian-incendiary-bomb-use-in-syria/