Something of a complex incident this one. Basically, Israel launched an air-strike on Iranian targets inside Syria, Syrian forces struck back and took out the Russian reconnaissance plane that was in the area and got too close to action that the Russians say they were unaware of.
Sadly, 15 crew appear to have died.
Russia has said Syria shot down one of its military planes - but laid the blame for the deaths of the 15 personnel on board with Israel.
The defence ministry said Israeli jets put the Il-20 plane into the path of Syrian air defence systems on Monday after failing to give Moscow enough warning of a strike on Syrian targets.
https://www.bbc.co.uk/news/world-europe-45556290
A million great ideas...