Homs, Syria, Torn By Fighting

Government vs. Hezbollah

BEIRUT—Syrian state forces backed by the Lebanese militant group Hezbollah hammered the central city of Homs on Friday, activists said, sparking concern from United Nations officials over thousands of civilians trapped in the city.

President Bashar Assad's forces have been using heavy air raids and artillery strikes to push their offensive around the capital and the strategically located Homs, which spans central Syria's eastern and western international borders.