Aleppo connection to shootingpublished at 17:48 Greenwich Mean Time 19 December 2016
The gunman - whose identity is not known - was heard shouting: "Don't forget about Aleppo, don't forget about Syria!"
Russia - a key ally of Syrian President Bashar al-Assad - has been accused of killing civilians during air strikes on the Syrian city of Aleppo, which is now controlled by Syrian government troops.
Protest rallies have been held near Russian embassies in a number of countries around the world.
Russia has repeatedly denied the allegation, saying it is targeting radical Islamists.