Alalam - Russia
The S-400 Triumph air defense system has been providing air cover for Russian forces in Syria since November, and is now being deployed on home soil.
It is capable of hitting moving airborne targets including planes and incoming missiles and has a range of 400km.
The news has emerged the day the US sent more than 3,000 troops to Poland in response to Nato's concern Russia was becoming more aggressive.
The S-400 air defence system has been providing air cover in Syria since November 2016
Defense Ministry’s Department of Information and Mass Communication told Interfax: 'The SAM combat squads of the Moscow Region aerospace forces have put the new S-400 Triumph air defense missile system into service, and have gone on combat duty for the air defense of Moscow and the central industrial region of Russia.
'The main task of the anti-aircraft missile troops of the Russian Aerospace Forces is air defense and protecting vital state, military, industry and energy facilities, as well as the Armed Forces troops and transport communications, from aerospace attacks.'
The S-400 was designed as a protective mechanism against airstrikes. according to RT.
The US tanks and armoured vehicles have started arriving in Poland today as part of the biggest American military reinforcement in Europe for decades, according to the BBC.
Soldiers will carry out exercised in the Baltics as part of their tour as part of the Obama administration's response to Russia's intervention in the Ukraine.
Tours will last nine months before troops rotate, but whether or not they will remain under Trump's regime remains to be seen.
President-elect Donald Trump's choice for secretary of defense is retired Marine General James Mattis.He is widely admired within defense and foreign policy circles.