For the first time in over two-and-a-half years, the women of Manbij, Syria walked with their faces uncovered Saturday, some of them even setting their niqabs on fire. Men shaved or trimmed their beards. Smokers of both sexes lit up and puffed away.

U.S.-backed fighters seized the key northern Syria city late Friday after two months of heavy fighting that killed more than 1,000 people and displaced thousands more. The fighters also freed hundreds of civilians the extremists had used as human shields, Syrian Kurdish officials and an opposition activist group said.

Amateur videos showed civilians hugging fighters from the predominently Kurdish Syria Democratic Forces (SDF) after being evacuated from the final ISIS-held neighborhood.

"May God destroy them. They slaughtered us," a young man shouted in a Manbij square. "May they not live for a minute."

In a photo posted online by Kurdish activists, a young woman defiantly uncovered her face while smoking a cigarette and flashing a victory sign.

ISIS imposes a harsh and extreme version of Islam on the territory under its control, including a mandatory dress code. Women had to wear long black cloaks that covered all but their eyes, while all adult men were forced to grow beards. Smoking was banned on penalty of fines or public flogging.

The capture of Manbij is the biggest defeat for the extremist group in Syria since July 2015, when they lost the town of Tal Abyad on the border with Turkey. The capture of Tal Abyad deprived the militant group of a direct route to bring in new foreign militants or supplies.

Manbij is important because it lies on a key supply route between the Turkish border and the city of Raqqa, the de facto capital of the ISIS group's self-styled caliphate.

Manbij had been under ISIS control since January 2014, when the extremists evicted other Syrian militant groups from the town.

ISIS' loss of Manbij followed two months after they lost the Iraqi city of Fallujah.

SDF spokesman Nasser Haj Mansour told The Associated Press that the town of Manbij "is under full control," adding that operations are ongoing to search for any ISIS militants who might have stayed behind. The SDF launched its offensive in late May to capture Manbij, and was supported by U.S.-led airstrikes.

Haj Mansour said some ISIS fighters were captured in the town while others fled to nearby villages.

"Military operations will continue until these villages are clean," Haj Mansour said.

Sherfan Darwish, another SDF official in Manbij, also confirmed that the town is under the full control of his fighters.

Rami Abdurrahman, who heads the Syrian Observatory for Human Rights, a Britain-based monitoring group, said the remaining ISIS fighters in Manbij left last Friday along with hundreds of civilians in some 500 vehicles heading in the direction of the city of Jarablus, on the border of Turkey.

Kurdish officials did not respond to requests for comment on whether the ISIS fighters were given a safe route to leave Manbij. During the offensive, the SDF had offered fighters a safe route to leave the town but they refused.

The Observatory said that following the capture of Manbij, hundreds of civilians used by ISIS as human shields have been freed.

SDF fighters had been slowly advancing on the town and nearby villages for weeks.

According to the Observatory, the fighting and the airstrikes have killed 1,756 people, including 438 civilians, 299 SDF fighters and 1,019 militants since the Manbij offensive began in late May.

Among those killed was the top Kurdish commander, known as Abu Layla, who died on June 5, days after sustaining wounds during the campaign.

ISIS has suffered major defeats over the past months in Syria and Iraq, where the military recaptured the cities of Ramadi and Fallujah in the western Anbar province. However, ISIS still controls large parts of Syria as well as Iraq's second largest city, Mosul.

The Associated Press contributed to this report.

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