China has increased its submarine presence in the Indian Ocean, worrying many neighboring countries and leaving India scrambling to beef up its navy.
The move comes shortly after a border standoff occurred between India and China in the Himalayas, and Chinese submarines have recently visited the island nation of Sri Lanka, located off the southern coast of India, and the Maldives, reported Reuters.
"We should be worried the way we have run down our submarine fleet. But with China bearing down on us, the way it is on the Himalayas, the South China Sea and now the Indian Ocean, we should be even more worried," said Arun Prakash, former chief of the Indian navy.
"Fortunately, there are signs this government has woken up to the crisis," he said. "But it will take time to rebuild. We should hope that we don't get into a face-off with the Chinese, that our diplomacy and alliances will keep things in check."
Indian Prime Minister Narendra Modi was prompted to accelerate the building of six diesel-electric submarines at a cost of $8.1 billion, and also has an order of six submarines being assembled by French firm DCNS, Reuters reported.
Four-fifths of China's oil imports pass through the area.
However, China insisted its submarines were merely refueling during anti-piracy runs in the Indian Ocean and Gulf of Aden, reported Voice of America.
As of now, India only has 13 submarines, and only half of them are operational at any given time. China is believed to have 60 conventional subs and 10 nuclear-powered, three of which are armed with nuclear weapons.
India is building its navy to about 150 ships, including only two aircraft carriers, while China currently has around 800 ships in its fleet.
Japan, with 16 subs, is also adding six more diesel-electric attack subs to its fleet, and is selling up to 12 stealth subs to Australia. Vietnam is in the market for up to four Kilo-class subs to add to its current two, and Taiwan is hoping to acquire U.S. technology to build out its own fleet, Reuters reported.
According to a new report by the U.S.-China Economic and Security Review Commission, China is expected to have as many as 351 submarines and missile-equipped ships in the Asia Pacific by 2020, compared to the 67 that the U.S. will likely have in the same territory.
A 2013 Indian Defense Ministry report warned that China's expansion into the Indian Ocean was a "grave threat" and an attempt to control important seas.