Well, that escalated quickly.

ANKARA/MOSCOW (Reuters) – 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.

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.

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 area known by Turks as “Turkmen Mountain”, it said.