The protests came as manoeuvres involving more than 30 warships from the US, Australia, Japan, Singapore and India shifted into high gear, moving from the Bay of Bengal towards the Andaman and Nicobar archipelago.

The exercise was centred 300 kilometres from the Andamanese capital of Port Blair, where activists said the proximity of the nuclear-powered vessels could damage the archipelago’s fragile ecology.

“Our very own Indian Navy is constantly infringing into the fragile zone for exercises,” said Samir Acharya, who heads the Society of Andaman and Nicobar Ecology.

“This time the only difference is that five countries are involved,” he said as Vice Admiral Doug Crowder, commander of the US Navy’s Seventh Fleet, flew into Port Blair yesterday to oversee the wargames.

Thirty-eight of the palm-fringed archipelago’s 321 islands are inhabited and its pristine waters contain some of the world’s most breathtaking coral reefs and marine life — including hundreds of endangered species.

“We, the tribals of the Nicobar group of islands, strongly oppose the event as it’s going to disturb our ecology,” said Rashid Yusuf of the Nicobar Youth Association environmental group.

“It’s our experience that after each naval manoeuvre, marine life is deeply affected, with fish dying in huge numbers,” Yusuf said by telephone from Nancowrie island.

A number of the more remote southern Andamanese islands are kept off-limits to visitors in a bid to protect the tribes who inhabit them.

India, hosting the six-day exercise that began on Tuesday, says no live ammunition will be used and results of mid-sea mock battles will be computer-simulated.

Threat to coral reefs

But a spokesman for the Island Solidarity Front, an activist group, said in the archipelago’s capital Port Blair that “these vast machines are enough to create havoc with the coral reefs, many of which were partially dislodged by the tsunami” in 2004.

The joint exercises, one of the biggest ever peacetime military events, involve super-carriers USS Nimitz and USS Kitty Hawk, the nuclear-powered submarine USS Chicago and Indian aircraft carrier the INS Viraat.

Some 160 fighter planes are in the air over the Bay of Bengal, separated from the Andaman Sea by the archipelago, which is part of India.

Indian officials declined to comment on the exercises.

The archipelago is India’s most strategic military base in the busy Indian Ocean with Car Nicobar island near Indonesia armed with long-range fighter jets.

The exercises are also facing opposition from anti-US communist allies of India’s ruling Congress party, who denounced them as proof of “India’s growing subservience to the United States.”

MPs protest

Meanwhile, MPs of the Left, Samajwadi Party and the Telugu Desam Party (TDP) shouted slogans and held a sit-in outside the main entrance of Parliament House yesterday morning to protest against the ongoing five-nation naval exercises in the Bay of Bengal. The US is one of the five.

Almost 50 MPs took part in the 15-minute sit-in and raised slogans like "UPA government should come to its senses" and "Stop ties with imperialist forces". The MPs, led by Communist Party of India-Marxist's Sitaram Yechury and Brinda Karat, TDP's Yerran Naidu and the Samajwadi Party's Shahid Siddiqui held banners reading — "US Navy, hands off Bay of Bengal" and "Stop Naval Exercises".