Syrian Rebels Have Retreated From Parts of Aleppo

A heavy government assault has forced rebels to abandon some of their positions.

BEIRUT — Rebel forces in Aleppo, Syria's largest city, said on Wednesday that government forces had launched a ground assault, forcing them to pull back from parts of a key neighborhood because their ammunition was running low, as new disputes arose around the contentious issue of foreign military support for President Bashar al-Assad.