Conditions in northwest Syria 'at crisis point', aid groups say

Dozens of international aid groups have warned that humanitarian conditions in Syria's north west have reached a new "crisis point", as government troops push to retake the rebels' last stronghold.

The violence has effectively shattered a ceasefire negotiated by Russia and Turkey, in place since September. Russia has firmly backed President Bashar al Assad's government in the eight-year civil war, while Turkey has supported rebel factions.