Explainer: What are the clashes in Syria’s Deraa about?

Fighting has escalated in recent days between government forces and rebels in the key southern province.

Fighting between Syrian government forces and rebels is intensifying near Deraa, in what has been described as the heaviest clashes since the southern eponymous province came under government control three years ago. Fighting started when government forces fired artillery shells towards the former opposition hub of Deraa al-Balad in tandem with a ground offensive. Nearly half of the population of the rebel-held district fled the heavy shelling and ground battles, but the United Nations warned remaining civilians are cut off with dwindling supplies.