It appears that Turkey is quite serious in their threats towards Russia. Turkey did not approve the Russian bombing of terrorists in Syria near the Turkey border.
It was revealed that Ethnic Turks in Syria were bombed by the Russian military. Turkey threatened Russia to stop any further military operation or they will be faced with consequences.
Turkey is also against Russia supporting Syrian Kurds involved in the fight against ISIS. Even though Russia explained that they are only targeting Islamic State terrorists, Turkey and its allies accused Putin for attacking anti-Assad rebels.
NATO members are under obligation to respond to an attack on Turkey, in case Russia ever did that.
A meeting was held between the Russian ambassador and the Turkish foreign ministry in which Turkey requested a termination of Russian military operations in Syria close to the Turkish border.
Turkey has always supported the Syrian Turkmen who are fighting against Assad.
Turkish foreign ministry claims that Turkmen villages were bombed during the Russian airstrike.
Turkey is also against Russia providing arms and support to Syrian Kurdish forces fighting against ISIS terrorists in Syria.