FILE - In this undated file photo released by a militant website, which has been verified and is consistent with other AP reporting, militants of the Islamic State group hold up their weapons and wave flags on their vehicles in a convoy on a road leading to Iraq, while riding in Raqqa, Syria. Simultaneous attacks on the Islamic State-held city of Mosul in Iraq and Raqqa, the de facto IS capital across the border in eastern Syria, would make military sense: They would make it harder for the extremists to move reinforcements and deny them a safe haven. (Militant website via AP, File)
Why Raqqa matters
01:25 - Source: CNN

Story highlights

US-backed troops continue to close the net around ISIS' self-declared capital

ISIS has occupied the Syrian city since 2013

CNN  — 

Civilians in Raqqa faced uncertainty after ISIS ordered the evacuation of the Syrian city, and then rescinded the command.

Residents began to flee the city Sunday and take to higher ground after ISIS issued a statement warning of the expected collapse of the Euphrates Dam, according to local activist group Raqqa is Being Slaughtered Silently (RBSS).

RBSS said ISIS later announced via loudspeaker that the dam was fine and requested residents remain in the city.

Raqqa is the latest city targeted by coalition forces in their attempts to rid Iraq and Syria of the extremist group. The city, which is is the extremist group’s operational command headquarters, is now largely surrounded – its main supply routes cut off by advancing forces.

The activist RBSS posted videos that purport to show Raqqa civilians fleeing, with groups of people clamoring to leave the city by car and foot. It also posted pictures that allegedly show coalition aircraft targeting the dam, which would endanger the northern Syrian city should it fail.

The dam is 25 miles west of Raqqa and supplies electric power to a wide area of Syria, according to the US. The area has been under ISIS control since 2013.

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Key airbase recaptured

US-backed troops continued to close the net around Raqqa, which ISIS has occupied for since 2013.

On Sunday the SDF, a coalition of mostly Kurdish and Arab militia, assumed control of Tabqa airbase from ISIS, about 50 kilometers west of Raqqa, according to a group spokesman and the London based monitoring group Syrian Observatory for Human Rights.

Backed by coalition warplanes, the fighters “took control of wide parts of the airport and cut the road between Salamia and Tabqa,” SOHR said.

Clashes between the SDF and ISIS in the town of Tabqa are still ongoing, SDF spokesman Talal Silo told CNN.

The base had been held by ISIS since August 2014 and was the site of an ISIS massacre that year when the jihadist group murdered more than 200 Syrian soldiers stationed at the airbase after marching them into the desert.

Late last week, France’s defense minister said, the battle to recapture Raqqa will begin in “days.”

“France has always said that Raqqa was a major objective,” Defense Minister Jean-Yves Le Drian said on French TV outlet CNews.

“Today, one can say that Raqqa is encircled, that the battle for Raqqa will start in the coming days. It will be a very hard battle, but a battle that is going to be of utmost importance.”

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Rebels: Dam not targeted by coalition

A US-backed rebel group which operates in the area – the Syrian Democratic Forces (SDF) – denied that coalition forces had caused any damage to the Euphrates Dam.

“We do not assess the dam to be in imminent danger unless ISIS plans to destroy it,” the rebel group said in a statement posted by the Combined Joint Task Force.

“(Tabqa) Dam has not been structurally damaged to our knowledge,” the statement continued, referring to the Euphrates Dam by another name.

“The Coalition seeks to preserve the integrity of the dam as a vital resource to the people of Syria.”

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‘Humanitarian crisis’

Should the dam fail, it could “could lead to a severe humanitarian crisis,” Col. Joseph Scrocca, a coalition public affairs officer, said last week.

Scrocca was speaking as fighters began a major ground offensive, backed up by US forces, to retake the vital dam from ISIS.

The attack also included an unprecedented air assault involving US helicopters landing behind enemy lines – flying about 500 local US allies and coalition military advisers across the Euphrates River and Lake Assad so they could attack the ISIS-controlled dam and neighboring town and airfield from the south.

“This is the first time we have conducted an air movement, air assault, with the Syrian Arab Coalition and Syrian Democratic Forces,” he said. On a call with reporters from Baghdad Wednesday, Scrocca called the air operation a “daring assault behind enemy lines.”

“We believe there are foreign fighters there, probably in the hundreds,” he said. “The (SDF) and our partners there are facing a pretty heavy fight – that’s what makes this type of operation so daring. I think we were lucky we caught ISIS by surprise. They are still reacting to this maneuver.”

CNN’s Ghazi Balkiz in Erbil, and Merieme Arif, Deborah Bloom and Susanna Capelouto in Atlanta contributed to this story.