Syrians from Raqa are seen in the city

Trapped in their homes in Raqa and running out of supplies, Ahmad Shaabu, his family and their neighbours were increasingly desperate. It was the children who finally helped them to escape.

Shaabu was among some 20 civilians who managed this week to flee the northern Syrian city, which a US-backed alliance of Kurdish and Arab forces are battling to take from the Islamic State group.

Tens of thousands of civilians are believed to remain in Raqa, seized by IS three years ago and turned into the jihadist group's de facto Syrian capital.

The alliance, known as the Syrian Democratic Forces (SDF), broke into Raqa on June 6 after a months-long operation to surround it and have since seized about a quarter of the city.

Fighting has been fierce but residents like Shaabu have been stopped from leaving by IS, which has been accused of using civilians as human shields.

"We couldn't get out... They wouldn't let us," Shaabu, 35, told AFP in Jazra, a western suburb of Raqa, after finally escaping on Tuesday.

Holding his small daughter in his arms, Shaabu described how his family and other residents were trapped in the western Raqa neighbourhood of Al-Daraiya.

"If we stepped outside we were targeted by snipers. They shot at me once when me and friends went out to fetch water," he said.

The families had gathered supplies but were running low and still had to risk leaving their homes, especially to get water. 

The streets were quiet on Tuesday and some of the smaller children -- free to roam without fear of being targeted by the jihadists -- were out when they were spotted by SDF fighters.

- Apocalyptic landscape -

"Our friends (the SDF fighters) saw the kids and started gesturing to them, and one of the children came and told us it was safe for us to get out," Shaabu said. 

Surce: AFP