Russian Defence Ministry’s Zvezda station reported Thursday that Russia has established a helicopter base in the northern Syrian city of Qamishli.

Video of the air base shows a pair of Mi-35 Russian attack helicopters and an Mi-8 landing at the base, along with an air defense system, among other systems and vehicles.

Russia’s move into the strategic Kurdish-controlled city comes as the U.S. continues to withdraw American troops from the region. Secretary of Defense Esper has said at least 500 to 600 U.S. troops will remain in the country to assist anti-ISIS efforts and to protect oil from falling into the hands of a resurgent ISIS.

But a drawdown of U.S. troops in Syria is still underway, despite videos and images online of American Bradley armored vehicles from the 30th Armored Brigade Combat Team patrolling Syrian roads.

CBS News reported, citing U.S. defense officials that the U.S. has completed its withdrawal from Kobani, which served as a key hub for anti-ISIS operations in Syria and as the central spoke for withdrawing forces from Syria.

It’s unknown if American troops are still in Qamishli, a question posed to the Pentagon and Operation Inherent Resolve regarding the status of U.S. troops in the city has yet to be answered.

“We’re aware of reports that Russia is setting up a helicopter base near Qamishli. The United States plans to remain in northeast Syria and will continue hunting ISIS wherever they hide," a U.S. defense official told Military Times on background.

“The U.S. will continue to de-conflict military operations with the Russian military, and we call on the Russian military to de-conflict their operations with us to keep all troops safe and avoid miscalculation,” the U.S. defense official said.

U.S. forces had a presence in Qamishli prior to Trump’s October decision to withdraw U.S. troops from northern Syria. The status of those forces is unknown.

But Agence France-Presse reported that American troops arrived in the Kurdish controlled town of Qamishli on Nov. 2 and met with SDF officials. AFP said the U.S. was interested in reestablishing a military post in the city.

U.S. forces were amid a pullout of northern Syria until Trump slightly walked backed his decision and agreed to keep a residual force to protect Syrian oil wells.

Trump has argued his decision to pull American forces was to keep them out of the crossfire of combative allies.

Turkey launched military operations into northern Syria on Oct. 9 to rout U.S.-backed Kurdish allies that Turkey believes is a terrorist group.

The decision to protect oil wells in Syria has come under criticism with some analysts and national security experts opining that the mission has unclear objectives — potentially putting U.S. troops in harms way with convoluted rules of engagement.

A number of major players packing armored vehicles and artillery are operating in the tightly congested northern Syria arena to include Russian, Turkish, and Syrian regime forces.

On Wednesday, when pressed by reporters about how oil mission relates to defeating, Esper said denying revenues to the terror group was important to ensure they couldn’t generate revenues.

“If they can generate revenue, then they can pay fighters, they can buy arms, they can conduct operations. They can do all those things because the revenue enables them. So that’s how the mission relates,” Esper told reporters as he was headed for Seoul.