This morning, news outlets are reporting that Turkey shot down a Russian Sukhoi fighter jet somewhere along the Turkey-Syria border.
According to Turkey, they warned the fighter jet it was "repeatedly' crossing into Turkish airspace and had been warned before it was attacked. Russia says the aircraft was well inside Syrian airspace and has promised "serious consequences."
Russian President Vladimir Putin said the plane had been attacked when it was 1 km (0.62 mile) inside Syria and warned of "serious consequences" for what he termed a stab in the back administered by "the accomplices of terrorists".
"We will never tolerate such crimes like the one committed today," Putin said, as Russian and Turkish shares fell on fears of an escalation between the former Cold War enemies.