In the already turbulent conditions over the Arabian Sea, this is by far the most alarming incident in recent years. The Indian Navy had a big alert last month when China's deadliest attack submarine crept past Indian waters and docked in Karachi.

According to exclusive details available with India Today, China's Yuan Class 335 submarine crossed the Arabian Sea and entered Karachi port on May 22. The submarine with at least 65 crew members reportedly spent at least a week in Karachi refuelling and restocking before sailing back to China. The incident took place less than a week after Prime Minister Narendra Modi's wrapped up Beijing trip.

According to reports, on March 31 this year, China's deadliest conventional submarine set sail from its base on Hainan island in the South China Sea. The Yuan-class submarine '335', equipped with torpedoes, anti-ship missiles and an air-independent pro-pulsion that dramatically enhances its underwater endurance, entered the Gulf of Aden over a fortnight later. But it was 335's first port of call that caught the attention of the security establishment in South Block.

Beijing's first-ever deployment of a submarine to Pakistan signals a new cat-and-mouse game in the region. It must be noted that China will be selling some eight Yuan class submarines to Pakistan within the next few years.

On May 28, Navy chief Admiral RK Dhowan told reporters in New Delhi that India was "minutely" monitoring Chinese naval activity in the Indian Ocean. He signalled the start of a new great game over the world's most important water body.

According to a New York-based Council on Foreign Relations report, Pakistan has the fastest growing nuclear programme in the world. Its arsenal, built with the help of Chinese technology, stands at between 100 and 120 warheads, compared with China's 250 and India with between 90 and 100.

