What is happening on the Turkey/Syria border?

Thousands of refugees are fleeing the Syrian Civil war battle lines in Aleppo after a recent surge in the military operations by the government backed by Russian airstrikes.

Many have fled north towards the Turkish border, where they have not been allowed through.

BBC News looks at what is happening on the ground and the events that led to the current situation.

Video produced by Valery Eremenko and Dina Demrdash