Russian Mi-25 Hind helicopters follows the wrong road from Valuyki and ends up further north in Belgorod instead of Kharkiv on the other side of the border and bombs the oil depot.
There was reports of helicopters flying past Korocha just some 20 minutes before the attack, which would confirm that the Russian pilots were following the wrong road and both roads are looking somewhat similar on the map.
Russian Hind helicopter in Belgorod