WASHINGTON — It's a scenario many feared in the fog of Syria's multi-front war: a confrontation in which U.S. forces, responding to a provocation, kill Russian mercenaries or contractors on a crowded battlefield.
Russian news reports Tuesday described just such a scenario, with an unknown number of Russian military contractors killed in a ferocious U.S. counterattack last week, although Defense Secretary Jim Mattis and other U.S. officials said they had no such information on casualties and the Kremlin did not confirm it. U.S. officials also said the Russian government had lodged no complaint about Russian nationals having been killed.
What is not disputed is the fast-changing, often confusing nature of a battlefield in which forces of multiple countries are bumping up against one another, raising the prospect of violent collisions, whether intended or not, that could further inflame tensions between Moscow and Washington. Russian forces are supporting the Syrian government in its war with opposition groups while staying in daily contact with the U.S. to avoid deadly battlefield collisions. Separately, the U.S. is supporting a group of Syrian Kurds and Arabs, dubbed the Syrian Democratic Forces, fighting the Islamic State.
Also beyond doubt is the ferocious scale of the U.S. attack on Feb. 7, in response to what the U.S. military called a barrage of artillery and tank fire from several hundred "pro-regime" fighters in Deir el-Zour province, an area in eastern Syria where remnants of the Islamic State have converged among oil fields. Lt. Gen. Jeffrey Harrigian, commander of U.S. air forces in the Middle East, told reporters a broad range of U.S. air power was unleashed.
For more than three hours, American F-15E attack planes, B-52 strategic bombers, AC-130 gunships, Apache attack helicopters and Reaper drones fired on the attacking ground force, which Harrigian said was advancing under covering fire from artillery, mortars, rockets and tank rounds. He said the air power stopped the attackers' advance and destroyed an unspecified number of artillery guns and battle tanks. He gave no estimate of casualties.
"As the hostile forces turned west and retreated, we ceased fire," Harrigian, speaking from his headquarters in Qatar, said in a video teleconference with reporters at the Pentagon. He insisted the U.S. had not yet determined the nationalities of those in the attacking force.
Russian media said Russian private contractors were part of pro-Syrian government forces that advanced on oil fields in the Deir el-Zour province and were targeted by the United States. The reports cited activists who said that at least four Russian citizens were killed in Syria on Feb. 7.
The Russian Defense Ministry charged that the incident reflected a U.S. push to grab Syria's economic assets under the cover of fighting the Islamic State group.
Without mentioning the U.S. strike, Russian Foreign Minister Sergey Lavrov said Tuesday that "Americans have taken dangerous unilateral steps."
"Those steps look increasingly like part of efforts to create a quasi-state on a large part of Syrian territory — from the eastern bank of the Euphrates River all the way to the border with Iraq," he said.
The state Tass news agency on Tuesday cited Natalya Krylova, a municipal lawmaker in the town of Asbestos in the Urals, as saying local residents Igor Kosoturov and Stanislav Matveyev were killed in Syria on Feb. 7. The Interfax news agency reported that a Cossack group in the westernmost Kalningrad region said a member named Vladimir Loginov was killed in combat in the Deir el-Zour province. It also quoted Alexander Averin, the leader of extreme leftist group Another Russia, as saying that one of its activists, Kirill Ananyev, was killed by the U.S. strike near Khusham.
Russian media also cited unconfirmed claims that overall casualties could have been as high as 200 and Russians could have accounted for the bulk of them. Those claims couldn't be verified.
CIA Director Mike Pompeo was asked during a Senate Intelligence Committee hearing about reported Russian casualties. He said that was a matter for the Pentagon, but he added, "From an intelligence perspective, we have seen in multiple instances foreign forces using mercenaries in battles that will begin to approach the United States."
Mattis, speaking to reporters Tuesday while traveling in Europe, said he had seen news reports of Russian contractors being killed in that fighting, which he described last week as a surprising assault in light of obvious U.S. advantages, including overwhelming air power. On Tuesday he said, "I don't have any reporting" about Russian contractors being among the casualties. "I can't give you anything on that. We have not received that word" at key U.S. military headquarters, including the Pentagon.
President Vladimir Putin's spokesman Dmitry Peskov refrained from commenting on the reports about the deaths last week, saying Tuesday they need to be verified.
Asked whether Putin had raised the episode during a phone conversation with U.S. President Donald Trump on Monday, Peskov said Syria wasn't discussed.
Isachenkov reported from Moscow. Associated Press reporters Deb Riechmann and Josh Lederman contributed from Washington and Lolita C. Baldor from Brussels.