In a shock offensive, insurgents breach Syria's largest city for the first time since 2016

BEIRUT (AP) — Insurgents breached Syria’s largest city Friday and clashed with government forces for the first time since 2016, according to a war monitor and fighters, in a surprise attack that sent residents fleeing and added fresh uncertainty to a region reeling from multiple wars.

The advance on Aleppo followed a shock offensive launched by insurgents Wednesday, as thousands of fighters swept through villages and towns in Syria’s northwestern countryside. Residents fled neighborhoods on the city's edge because of missiles and gunfire, according to witnesses in Aleppo. The Syrian Observatory for Human Rights, which monitors the country's unresolved civil war, said dozens of fighters from both sides were killed.

The attack injected new violence into a region experiencing dual wars in Gaza and Lebanon involving Israel, and other conflicts, including the Syrian civil war that began in 2011.

Aleppo has not been attacked by opposition forces since they were ousted from eastern neighborhoods in 2016 following a grueling military campaign in which Syrian government forces were backed by Russia, Iran and its allied groups.