Some more info from Russian media.
The second pilot, the navigating officer, was rescued by Syrian Army (special forces). He is back now at the Russian base. The commander was awarded posthumously.
The Russian minister of defense has said that they are planning to send S-400 SA system to the Russian airbase of Khmeimim to secure the area in all directions. The president has approved it.
The Russian minister of defense has said that they have already taken certain counter measures against such hostile activities. In particular the missile cruiser Moskva (Moscow) has already taken its position in the sea westwards Latakia. Moskva is equipped with the Fort system (analogue of S-300) and ready to destroy any target recognized as threat.