600,000 return home

More than 600,000 displaced Syrians have returned to their homes since the beginning of the year, with most of them heading to Aleppo, according to figures from the International Organization for Migration.

Between January and the end of July, 602,759 displaced Syrians returned to their homes, many of them citing an improved economic and security situation in the areas they had fled from, IOM said in a statement.

A total of 84 percent of those who have returned had taken refuge elsewhere within the war-ravaged country, while the remaining 16 percent returned from neighbouring countries Turkey, Lebanon, Jordan and Iraq.

More than a quarter of returnees said they did so to protect their assets and properties, while nearly the same number referred to the improved economic situation in their place of origin, and 11 percent cited the improved security situation there.

Fourteen percent meanwhile pointed to the worsening economic situation in their place of refuge, IOM said.

But while most of the returns had been spontaneous, it warned they were "not necessarily voluntary, safe or sustainable," it said.

Aleppo Governorate, the scene of the harshest battles of Syria's bloody six-year war, had received 67 percent of all returnees so far this year, IOM said.

And within the governorate, Aleppo city, which was recaptured by the Syrian army last December after a suffocating five-month siege, has received most returnees, it said.

Many of those returning meanwhile must struggle to get bare necessities, with only 41 percent having access to clean water and 39 percent with access to health services.

The United States expressed sadness and horror Sunday over the killing of seven members of Syria's White Helmets rescue service in a jihadist-held town near Idlib.

The seven were killed Saturday by unidentified assailants in a raid on their base in Sarmin, nine kilometers (5.6 miles) east of the city of Idlib.

Meanwhile, US-backed fighters fought pitched battles Sunday with Islamic State group jihadists inside their Syria bastion Raqa.

The Syrian Democratic Forces, the Arab-Kurd alliance, first entered Raqa two months ago and have since captured more than half of the northern city, but their progress has met fierce resistance from IS.

A warplane from the US-led coalition provided air cover and bombed IS positions in the Old City, with plumes of smoke billowing into the sky.

"There is heavy fighting. Our forces are trying to surround more and more Daesh (IS)," said Nuri Mahmud, a spokesman for the Kurdish YPG militia that dominates the SDF.