A video obtained by Reuters on Tuesday purported to show a Russian pilot who appears to be lifeless or incapacitated on the ground, and an official from a Syrian rebel group told Reuters the man was dead.
Turkish fighter jets shot down a Russian warplane near the Syrian border on Tuesday after repeated warnings over air space violations, but Moscow said it could prove the jet had not left Syrian air space.
Footage from private Turkish broadcaster Haberturk TV showed the warplane going down in flames in a woodland area, a long plume of smoke trailing behind it. The plane went down in an area known by Turks as "Turkmen Mountain," it said.
Separate footage from Turkey's Anadolu Agency showed two pilots parachuting out of the jet before it crashed. A Syrian rebel group sent a video to Reuters that appeared to show one of the pilots immobile and badly wounded on the ground and an official from the group said he was dead.
The video was posted to social media websites, a portion of which was sent to Reuters by the rebel group, which operates in the northwestern area of Syria. Their territory includes where groups including Free Syrian Army are operating but Islamic State has no known presence.
Voices can be heard on the video as a group of men surrounds the incapacitated man.
"This is the Russian pilot, this is the Russian pilot. God is great," they say. "The tenth brigade has has captured the Russian pilot. God is great. There is only one God. All the mujahideen."
The official from the group, who declined to be named for security reasons, did not mention a second Russian pilot who was in the plane.
The military uniform of the incapacitated man in the video matches images previously released by the Russian Defense Ministry and Reuters file photographs of pilots from that country operating out of Hmeymim air base near Latakia in Syria.
It was the first time a NATO member's armed forces have downed a Russian or Soviet military aircraft since the 1950s and Russian and Turkish assets fell on fears of an escalation between the former Cold War enemies.
A Kremlin spokesman said it was a "very serious incident" but that it was too early to draw conclusions.