The submarine is being supported by Chinese Naval Ship (CNS) Chongmingdao - the Chinese Navy's submarine support vessel. (Picture for representation)

In an aggressive move, China has deployed a submarine in the Indian Ocean Region, as the month long stand-off in the Doklam plateau between the Indian and Chinese People's Liberation Army continues.

Wading through the Indian Ocean now is a Yuan class - conventional diesel electric - submarine which is better that aging Indian Sub. And this is not the first, but the seventh submarine to be deployed in the area.

The submarine is being supported by Chinese Naval Ship (CNS) Chongmingdao - the Chinese Navy's submarine support vessel. Indian assets picked up the submarine entering the Indian Ocean Region recently.

The Indian Navy has underlined the heightened Chinese People's Liberation Navy activity in the Indian Ocean Region to South Block. Chinese warships and submarines in Indian Ocean Region appeared three years ago 2013-14 - ostensible for anti-piracy operations in the Gulf of Aden.

But from a modest beginning of a flotilla of just three warships - two destroyers and a support ship - in 2013-14, more and more Chinese warships are prowling in the waters around India.

WAR GAMES

Recently, Indian satellites and naval assets have picked up at least 14 Chinese Navy warships in the Indian Ocean Region. These include the latest Luyang-III or the Kunming class stealth destroyers.

Armed with surface-air and long range missiles the Chinese warships are projecting power far away from the Beijing's backyard but in India's immediate vicinity. The silver lining - India is constantly monitoring the movement of Chinese warships courtesy Indian satellites and long range maritime surveillance platforms.

The Indian Navy's long range surveillance platforms like the US made P81 has been watching and recording movements of the Chinese Navy in the Indian Ocean. "Over the years, we have augmented our capabilities manifold. More force multipliers are being added. We have the region covered as well," a senior officer told India Today.

The first Chinese nuclear submarine was picked up in December 2013. The Shang Class- a nuclear propelled submarine-was deployed for almost three months in the waters around India till February 2014.

It was followed by Song Class - diesel electric -submarine for another three months between August and December 2014. The Song Class followed by another nuclear vessel - a Han Class nuclear submarine. Last year China deployed a nuclear submarine - a Han Class Nuclear submarine - and a conventional submarine respectively.

WORRYING SIGN?

These boats were snooped around the Indian Ocean for over six months. The Yuan class submarine detected by the Indian Navy this year is first the submarine to be sent to the Indian Ocean Region in 2017. Worryingly for India, the increased warship deployment goes hand in hand with the deployment of Hydrographic, Oceanographic vessels and spy-ships in the Indian Ocean to map the sea bed.

Bathymetric data among other things detail how currents and noise behave at particular depth, the lay of the ocean floor are critical for submarine deployments.

Top sources told India Today that Chinese Naval Ship Haiwngxing -spy ship -entered the Indian Ocean this month. The spy ship equipped with sophisticated equipment is deployed to collect electronic intelligence among other things. It is capable of honing on electronic signals which can be returned to China for analysis. New Delhi has been told that the spy ship is the Indian Ocean region to monitor the annual tri-lateral India-USJapan naval exercise - Malabar that starts on July 7. The same ship was used to spy on previous Indo-US Naval exercises.

ALSO READ | Chinese warships frequently visit Karachi, Gwadar in bid to expand presence in Indian Ocean

Presence of Chinese submarines in Sri Lanka purely for economic reasons: Navy chief Vice Admiral RC Wijegunaratne

China escalates border tension, accuses Indian Army of betrayal

ALSO WATCH | Centre napping, part-time Defence Minister will not work: Congress on border standoff with China