Russia Claims to Kill Hundreds of Militants in One Day as U.S. Battle Against ISIS Nears End

Russia said Wednesday its forces and Syrian troops killed up to 850 jihadists in a counterattack in rebel-held northeastern Syria. The news came shortly after U.S.-led fighters said their separate, increasingly rival campaign against the de facto capital of the Islamic State militant group (ISIS) was nearing its conclusion.

Both the Russia-backed Syrian military and the U.S.-backed Syrian Democratic Forces, a mostly Kurdish formation of Arabs and ethnic minorities, are battling various insurgent and ultraconservative Islamist groups that have attempted to take control of Syria since 2011. While ISIS has recently been the primary target of the dual offensives, Russian personnel were reportedly ambushed and surrounded by militants of Hayat Tahreer al-Sham, formerly known as Al-Qaeda's Nusra Front, near the northeastern city of Idlib. Three Russian special forces members were reportedly injured, but a top Russian general said the retaliation by his forces was devastating.

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"Aircraft were delivering strikes on terrorists, the unit breaking the encirclement was supported by two Sukhoi Su-25 aircraft that attacked militants and their armored vehicles from extremely low altitudes. As a result, the encirclement was broken and the Russian troops entered the area occupied by the Syrian government forces," Colonel General Sergei Rudskoi, head of the Main Operations Department at Russia's General Staff, said, according to the state-run Tass Russian News Agency.

"The steps that the Russian military command took together with the Syrian General Staff helped repel terrorists' offensive and inflict significant damage on them," he added.

Rudskoi went on to explain the operation in detail, saying it involved both Russian and Syrian special forces, as well as fighters from Russia's North Caucasus region. In a span of 24 hours, the Russian colonel general said 187 facilities were attacked and 850 militants killed, and dozens of other vehicles, weapons and sites were destroyed.

The attack took place in one of Syria's so-called de-escalation zones, outlined during an agreement signed Friday by Russia, Iran and Turkey amid peace talks in Astana. Russia and Iran support Syrian President Bashar al-Assad and his armed forces, while Turkey backs the anti-government Free Syrian Army. The Free Syrian Army's position has weakened throughout the six-year war due to the increased influence of jihadist groups such as ISIS and Hayat Tahrir al-Sham, which has defeated and absorbed a number of groups previously supported by the West.

After disowning Syrian opposition groups fighting Assad, the U.S. switched the focus of its support to the Syrian Democratic Forces and has led a 10-month campaign against ISIS's northern stronghold of Raqqa. While Syrian troops, along with Russian and Iranian allies, have brushed up against the Syrian Democratic Forces near Raqqa, the U.S. allies have spearheaded the assault on ISIS in the city itself and said Wednesday they have taken most of the area.

"We can say that 80 percent of the city of Raqqa has been liberated," the group said in a statement, adding that new, recently opened fronts against ISIS were "a feature of the final stages of the Euphrates Wrath campaign, which is nearing its end," according to Reuters.

The Syrian Observatory for Human Rights, a U.K.-based monitor with ties to Syria's opposition, told Newsweek that the Syrian Democratic Forces likely controlled "more than 90 percent" of Raqqa.

In addition to these campaigns, Syria's most recent front has forces backed by Russia and those supported by the U.S. on what observers fear could be a collision course in the east. After retaking most of central Syria, the Syrian military fought its way to the eastern city of Deir Ezzor, ultimately breaking a three-year ISIS siege against fellow soldiers encircled by the jihadists.

The Syrian Democratic Forces, however, have also advanced from the north, battling ISIS on the other side of the Euphrates River from Syrian troops and their Russian and Iranian allies. While the U.S. said Thursday it would stand back and allow the Russia-backed offensive to tackle ISIS in its last major city of control, Rudskoi said during Wednesday's remarks that he suspected U.S. intelligence of helping to orchestrate the Hayat Tahrir al-Sham attack to distract from the Russian and Syrian initiative in Deir Ezzor.

Like the Syrian government, the Syrian Democratic Forces reject the Islamist ideologies of ISIS and Al-Qaeda, as well as the Free Syrian Army, mainly due to its ties to Turkey. The U.S.-backed force, however, demands greater autonomy for the country's north, considered by Kurds to be part of their homeland, while the Syrian military wants to see full control of the country restored to Assad.