NATO’s North Atlantic Council met for an emergency session on Tuesday after Turkish jets shot down a Russian Su-24 warplane close to the Syrian border.

It was the first time a NATO country has downed a Russian military plane since the 1950s.

The alliance’s secretary general, Jens Stoltenberg, told reporters after the meeting, “We stand in solidarity with Turkey and support the territorial integrity of our NATO ally.”

Earlier in the day, Turkish television had shown a jet going down in flames north of Latakia, the Syrian city from where Russian aircraft have been operating.

The two pilots parachuted out before the plane crashed. One was reportedly killed by Turkmen forces in the area and the other captured.

Repeated warnings

Russian president Vladimir Putin insisted that the plane was inside Syria when it was attacked and warned of “serious consequences” for what he called a “stab in the back by the accomplices of terrorism.”

But Turkey said its F-16s had repeatedly warned the Russians they were violating Turkish airspace and the Su-24 did not respond.

Stoltenberg said assessments from other NATO member states confirmed that.

The pilot of a commercial airliner flying nearby overheard the Turkish warnings and told the Netherlands’ RTL News that the F-16 crews indeed warned the Russian plane before it entered their nation’s airspace.

“The plane was hailed literally dozens of times by the Turks, but there was no response,” the pilot said.

A radar image released by Turkey’s military also showed the Russian jet veering into its territory, if briefly.

Escalation unlikely

Experts don’t expect either Russia or Turkey will significantly ratchet up tensions.

Daniel Drezner, a professor in international politics at Tufts University, argues in The Washington Post that “Russia and Turkey are sufficiently interdependent that a serious heightening of tensions would severely impair both countries.”

Turkey would find it very difficult to suddenly stop using Russian natural gas. Russia would find it very difficult to not use the Dardanelles.

Mark Galeotti, a New York University professor and Russia analyst at the crowdsourced consultancy Wikistrat, is slightly less upbeat. He predicts an uptick in Russian mischief: “perhaps some support for the Kurds or other violent extreme movements, for example, as well as a more assiduous campaign to push back and stymie Turkish regional ambitions.”

But he doesn’t expect the situation to spiral out of control either. “I suspect neither Moscow nor, at the very least, the other European NATO powers will want to let this go too far,” he writes.

Crowded skies

Turkey earlier shot down an unmanned drone suspected to be Russian in October.

Russian jets started bombing in Syria a month earlier in support of the regime of President Bashar al-Assad. They often hit rebel targets in the western part of the country where Assad holds most territory. Much of the east of Syria is controlled by the self-declared Islamic State, the target of Western airstrikes.

Turkey has backed the opposition forces Russia now bombs since the uprising against Assad started in 2011.

One of its jets was shot down by the Syrian army over the Mediterranean Sea in the summer of 2012 after it had crossed into Syrian airspace. Two pilots were killed.