Flyers usually address ISIS fighters, telling them that his time has come to an end. (File Photo)
The US-led coalition fighting the ISIS has dropped flyers on Syria's Raqa urging residents for the first time to leave the jihadist stronghold, an activist and a monitor said Friday.
"It's not the first time that coalition airplanes have dropped flyers on Raqa but it's the first time that they've addressed residents and asked them to leave," a founding member of the citizen journalist group Raqa is Being Slaughtered Silently (RBSS) said.
Flyers usually address ISIS fighters in the city, telling them "Your time is coming, your end is coming", Abu Mohammad said.
On its Facebook and Twitter accounts, RBSS shared an image of what they said was the flyer dropped on the jihadists' de facto capital in Syria.
"The time you have been waiting for has come, the time has come to leave Raqa," reads the top of the comic book style water-coloured sketch.
It shows residents -- three men wearing backpacks, a veiled woman and a child -- fleeing a grey battered city into an idyllic green countryside, running past dead soldiers and ISIS fighters and a sign marked: "ISIS, Raqa province, checkpoint".
Abu Mohammad said that ISIS fighters in Raqa were increasingly using residents as human shields against coalition air strikes.
"Their positions used to be clear but since the beginning of the air campaign against them, they've started to resort to hiding among civilians," he said.
At least 408 civilians have died in coalition air strikes in Syria since they began in 2014, according to the Syrian Observatory for Human Rights.
"It's the first time residents have been advised to leave the city," Observatory chief Rami Abdel Rahman said.
But "these flyers are just a part of the propaganda campaign against ISIS," he added.
Kurdish forces, which control a swathe of territory north of Raqa, are regarded by Washington as the most effective fighting force against ISIS in Syria and have received US military support.
"There has been information circulating about the Kurds preparing a campaign against ISIS in Raqa with the support of the international coalition," Abdel Rahman said.
But "that's not likely now because (retaking) Raqa will require planning a massive battle, and huge preparation of fighters and popular support," he said.
"If the extremist group had feared a battle against it in Raqa, it wouldn't have sent its best fighters to take part in fighting in the north of Aleppo province."
ISIS and its jihadist rival Al-Qaeda are not party to a February ceasefire between government forces and other rebel groups.
Air strikes against them have continued, not only by the coalition but also by the Syrian government and its ally Russia.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)