Fierce clashes in IS bastion

US-backed fighters yesterday battled the Islamic State group as they tried to push further into the jihadists' Syrian bastion Raqa, two days after finally entering the northern city.

The Syrian Democratic Forces alliance of Kurdish and Arab fighters began the battle for the city earlier this week after seven months of fighting to surround the jihadist stronghold.

On Wednesday, an AFP journalist entered the city with SDF fighters and witnessed heavy clashes in the Al-Meshleb neighbourhood, with IS firing multiple mortar rounds towards the advancing forces.

He said part of the neighbourhood was under SDF control but US-led coalition planes were still carrying out strikes against IS fighters elsewhere in the district, one of the largest in Raqa.

SDF fighters were armed mostly with light weapons including Kalashnikovs, and were also returning mortar fire on IS positions.

The SDF did not allow journalists to return to the city yesterday where fighting was continuing.

"Our troops are advancing in Al-Meshleb and control parts of it," SDF spokesman Talal Sello told AFP.

"The international coalition forces are working with use on the ground in the battle for Raqa in a highly effective manner," he added.

The US-led coalition said it had carried out 22 strikes near Raqa on Wednesday, hitting IS fighting positions and vehicles as well as a weapons cache and a training camp.

The Britain-based Syrian Observatory for Human Rights monitor said the SDF now controlled around two-thirds of Al-Meshleb and was some 400 metres (yards) from the neighbouring Al-Senaa district.

"IS has snipers monitoring Al-Meshleb neighbourhood and has laid mines extensively throughout it," the Observatory said.

The group said the district had been emptied of its civilian population before the SDF entered, and IS had dug defensive trenches and tunnels in the area in a bid to hold off attacking forces.

Fighting was also continuing on the western outskirts of the city, the monitor said, adding that US special forces were actively participating in battles on several fronts.

Around 500 US military personnel, not all of them special forces, are believed to be participating in the battle for Raqa.

Captured by the jihadists in 2014, Raqa has become synonymous with IS atrocities including beheadings and public displays of bodies, and also emerged as a hub for planning attacks abroad.

An estimated 300,000 civilians were believed to have been living under IS rule in Raqa, including 80,000 displaced from other parts of Syria.

But thousands have fled in recent months, and the UN humanitarian office estimates about 160,000 people remain in the city.

Civilians trapped in Raqa also face the risk of heavy coalition air strikes.

The number of reported civilian casualties in the coalition's strikes has swelled as the SDF offensive has intensified.

Along with Mosul in Iraq, Raqa was one of the twin pivots of the self-styled Islamic "caliphate" that IS declared nearly three years ago.

Elsewhere in Syria, there has been a sharp reduction in fighting in the past month after rebel supporter Turkey, Russia and fellow regime backer Iran brokered a deal to set up safe zones in four key battlegrounds.

The three sponsors had been due to meet with regime and rebel representatives in Astana next week to shore up the deal but the Kazakh foreign ministry said that the talks had been postponed.