Russia condemned the downing of a warplane on the Turkish-Syrian border but refused to comment further after Ankara said it had shot down the plane. "It is a very serious incident," Kremlin spokesman Dmitry Peskov told reporters. "It would be wrong to make some assessments, proposals or announcement when we don't have the full picture." Turkey's Foreign Ministry summoned the Russian charge d'affaires on Tuesday as NATO was holding an emergency meeting. Tuesday's meeting of the North Atlantic Council, the alliance's main decision-making body, was being held at Turkey's request. The incident is the first time a Russian or Soviet plane has been shot down by a NATO member since 1950s. The Turkish military said the jet was repeatedly warned that it had violated Turkish airspace, but this is disputed by Moscow. With a major diplomatic crisis looming between two states on opposing sides in the Syria conflict, Russia insisted the jet was all the time inside Syrian airspace. Turkish media said one pilot had been captured by rebel forces in Syria after both ejected by parachute while Syrian opposition sources said one was dead and another missing. The fighter jet exploded in mid-air, crashing in a fireball onto a mountain on the Syrian side of the border, television pictures showed. The Turkish army said that the downing took place over the Yayladagi district of Turkey's Hatay province on the border with Syria. "The plane violated Turkish air space 10 times in five minutes despite warnings," the army said in a statement, adding it was shot down by at 0724 GMT "according to the rules of engagement."