DARAYA, Syria (AP) — Escorted by armed troops, dozens of insurgents and their families left this war-wrecked suburb of the Syrian capital on Friday as part of a forced evacuation deal struck with the government to end a four-year siege and aerial campaign that has left the area in ruins.

The capitulation by rebel forces in Daraya, an early bastion of the uprising against President Bashar Assad, provides another boost for his forces amid a stalemate in the fight for Aleppo, Syria’s largest city.

It also improves security around Assad’s seat of power, pacifying an entire region southwest of Damascus that was once a backbone of the rebellion. Daraya was the last remaining rebel holdout in the region known as western Ghouta – and the closest to the capital.

The mass relocation of the suburb’s residents reflects the government’s ongoing military strategy to break up Sunni population areas, weakening the rebellion against it.

It also highlights concerns over the forced displacement of members of the Sunni majority, seen by some as a government policy to strengthen its base and create a corridor made up of its minority supporters.

Following the deal struck late Thursday, Daraya’s rebels began evacuating in government buses on Friday, a process expected to take several days. Around 700 gunmen are to be allowed safe passage to the opposition-held northern province of Idlib, while some 4,000 civilians will be taken to temporary shelter in government-controlled Kisweh, south of Daraya.

The U.N., which said it was not consulted over the plan, expressed concern over the evacuation, saying it was imperative that those participating do so voluntarily.