MOSCOW, Jan. 11 (Xinhua) -- An air defense regiment of the Russian Airspace Forces stationed in the Moscow region has started combat duty after receiving the sophisticated S-400 missile systems, the Russian Defense Ministry said Wednesday.

The ministry said in a statement that another S-400 missile system is on its way to the region after passing a successful combat test.

Russian Airspace Forces received four S-400 systems in 2016 within a re-equipment program and will receive another four this year, the ministry added.

The S-400 Triumf, first commissioned in 2007, is a new generation of anti-aircraft missile system capable of hitting airborne targets at a distance of up to 400 km.

Russia deployed one S-400 system at its Hmeimim air base in Syria in November 2015, after Turkey downed a Russian jet on the Syrian-Turkish border.