MOSCOW, January 11. /TASS/. Four S-400 anti-aircraft missile systems will enter service in Russia’s Aerospace Forces this year, the Defense Ministry said on Wednesday.

"A total of four air defense regiments were re-equipped with the S-400 Triumf anti-aircraft missile system in 2016. Another four S-400 systems will enter service in the Aerospace Forces in 2017," the ministry said.

The ministry added a regiment equipped with the new S-400 Triumf air defense missile system has taken up combat duty in the Moscow Region.

The new missile system arrived in the Moscow Region from a firing range in Kapustin Yar in the Astrakhan Region, southern Russia, after successful firing exercises.

"As part of re-equipping the Aerospace Forces by modern and advanced missile defense systems another regiment-size set of S-400 Triumf system entered service in one of the Moscow Region’s air defense task forces of the Aerospace Forces," the ministry said.

Another air defense regiment equipped with the S-400 system will be put on combat duty in the Moscow Region soon after being redeployed from the Kapustin Yar range, the ministry said.

The ministry said that the key task of the air defense missile regiments is to protect the airspace over the country’s important state administration and military control centers, industrial and energy facilities, the Armed Forces units and transport infrastructure from the adversary’s attacks.

Last year, Russian arms manufacturer Almaz-Antey supplied to the Defense Ministry five regiments of this system.

The S-400 Triumf is the most advanced long-range anti-aircraft missile system that went into service in 2007. It is capable of destroying aircraft and cruise missiles at a distance of up to 400 km and ballistic targets flying at a speed of 4.8 km per second - at a distance of 60 km.