ISIS 'caliphate' near collapse as most of Raqqa taken by U.S.-backed forces

Jim Michaels | USA TODAY

Show Caption Hide Caption U.S.-backed troops breach the perimeter of ISIS' last bastion in Syria U.S.-backed forced have breached a perimeter wall that surrounds the Old City of Raqqa, reportedly the last stronghold of the Islamic State (ISIS) in Syria.

The end for the Islamic State's self-proclaimed caliphate is near, three years after the terrorist group announced its vision for creating a nation state across Iraq, Syria and the wider region.

U.S.-backed forces are on the verge of capturing the group's home base, Raqqa, Syria, the last major city it still holds.

A U.S.-led coalition has captured 70% of Raqqa, prompting rare surrenders by some fighters for the Islamic State, or ISIS, the coalition said.

The number of fighters remaining in the city is between 500 and 900, down from 3,500 at the start of the offensive in June, the coalition said.

Still, the remaining fighters have put up a stiff resistance in dense neighborhoods, which have been packed with hidden explosives. The militants also have made extensive use of tunnels, suicide bombers and truck and car bombs.

Over the past two months, about 30 fighters have surrendered to the U.S.-backed Syrian Democratic Forces (SDF).

The surrenders suggest ISIS is struggling and is unable to prevent fighters and their families from fleeing, said Army Col. Ryan Dillon, a U.S. military spokesman.

Normally, the leaders prevent defections by executing those who try to escape, but the leadership may now be in disarray.

Foreign fighters are the most committed to ISIS, unlike local recruits who often are forced into its ranks or lured for pay. The latter group are more likely to defect.

Those who have surrendered have said they have become disillusioned with the caliphate, Dillon said.

Some of the fighters who surrendered were clutching leaflets dropped by coalition aircraft explaining how to escape the fighting.

The SDF is backed by coalition airstrikes, artillery and several hundred advisers.

The Raqqa offensive follows another major campaign by U.S.-backed forces to recapture Mosul, Iraq's second-largest city, which was retaken in July after more than six months of intense fighting.

Even after the expected fall of Raqqa in coming weeks, small pockets of resistance remain, mainly in a string of towns along the Euphrates River from Syria to western Iraq. Iraq's military has begun operations to retake some of those towns.

These rural area will be difficult to recapture. "You can't really just contain the whole Euphrates River valley and starve them out," said Army Lt. Gen. Stephen Townsend, who recently stepped down as the top coalition commander for Iraq and Syria. "It's too big."

The group also still controls, Hawija, a town in northern Iraq. U.S.-backed Iraqi forces began an offensive there Thursday.

The fighting along the Euphrates River in Syria has required intensified U.S. military consultations with Russia's military to avoid mishaps as forces converge in the area.

Russian advisers and aircraft are supporting the Syrian government in its civil war with rebel groups, and the Russians generally operate on the western banks of the river. The U.S.-backed SDF is operating on the opposite bank.

This week, a coalition general met with a top Russian general in an undisclosed location in the region to discuss establishing separate areas for the two sides to operate, Dillon said.

The Russians and coalition have also established regular telephone calls to discuss air and ground operations in an effort to avoid mishaps.

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