Watch: India's S-400 missile system in action from April to counter China at LAC

India has begun work on deploying the S-400 Triumf advanced surface-to-air missile defence system, with the first unit to be made operational in April. While the Narendra Modi government remains tight-lipped about the entire project, officials with direct knowledge of the matter have told Hindustan Times that all five units will be deployed in depth areas to tackle the threat from China. HT learns that India has made clear to its close ally US through top diplomatic and security channels that the acquisition of Russian S-400 system was in its national interest as it is faced with a belligerent PLA all along the 3,488km-long LAC. Watch this video for full details.