This was reported in the press service of the Russian Defense Ministry.

“Combat crews of the S-400 anti-aircraft missile system of the Eastern Military District (VVO) have taken up combat duty for air defense,” TASS reports.

As noted, the military "began to carry out tasks to control the airspace in the established area of ​​​​responsibility."

Earlier it was reported that the Russian long-range air defense system (air defense) S-400 "Triumph" was deployed at a training ground in the Brest region as part of the exercises of the Union State.

On February 3, divisions of the S-400 Triumph anti-aircraft missile systems participating in the test of the reaction forces of the Union State arrived in Belarus. 

Russia, as part of the test of the reaction forces of the Union State, also transferred Pantsir-S anti-aircraft missile and gun systems to Belarus.