内容摘要："If you start at the top you just cling on and learn very quickly."

"If you start at the top you just cling on and learn very quickly."

Nikkita Holland, 31, who is from Doncaster but holidaying at Butlin's, tells her young daughter to keep away from the clumps."It's quite shocking," she says. "I didn't know what it was. It doesn't look great."

Further up the beach, I spot several dead seabirds. It is impossible to know if they had consumed the material.Dennis Simpson, 77, and his wife Gill, 70, have also noticed the dead birds."We've counted three," says Mrs Simpson. "We don't usually see dead seabirds on this beach."

Mr Simpson adds: "We thought something would wash up here."His wife was volunteering in the RNLI shop, close to the beach, when the crash happened.

"Everyone was running around all over the place," she recalls.

Sharon Glenville, 60, who is walking her two dogs, tells me she thought the clumps were pieces of coal. Her face drops when I tell her what it is.But HTS's ambitious high-profile leader has seized the spotlight. His rhetoric and record are now under scrutiny by Syrians, as well as in neighbouring capitals, and far beyond. The commander whose militia first emerged as an Al-Qaeda affiliate broke ranks with the jihadist group in 2016 and has been trying to polish his image since then. For years, he's sent conciliatory messages abroad; now he is reassuring Syria's many minority communities they have nothing to worry about.

"There is a cautious welcome to his messages," maintains Ms Forestier. "But we cannot forget the past eight years of his authoritarian rule and his background." The rule of HTS, both a political and paramilitary organisation, in the conservative province of Idlib was marked by the establishment of a working administration called the Salvation Government, which included limited freedom of religion, but was also marked by repressive measures.In Syria's second city of Aleppo,

, its fighters have been trying to prove they are fit to rule.The group has also been sending reassuring messages to countries like Iraq that the war would not spill across their borders. Other neighbours, including Jordan, worry that Islamist successes next door could galvanise disgruntled militant groups within their borders. Turkey, certain to play a key role, has its own worries. It regards the SDF as a terrorist group linked to Turkey's proscribed PKK Kurdish group and will not hesitate to intervene militarily and politically, as its done for years, if its own interests are threatened.