Multiple warhead shells, like Cluster bombs for cannons controlled by a radar altimeter and set to go off a specific altitude vary similar to shells used in flak cannons during WWII.
Gotcha, but ... (remembering I know nuthin about arty) The smoke trails behind the ‘stars’ imply a slow descent through the atmosphere. Cluster bomblets don’t fall slowly or ‘burn’ in the air as they descend.
Am I off base here?
Just tryin’ to get to the bottom of it ... and burn Reuters of course.