Updated

India's refusal to allow access to the remote Andaman and Nicobar islands (search) is preventing aid from reaching the most desperate survivors of last week's tsunamis, international aid groups said Monday, as the country's death toll was expected to top 15,000.

Despite the Dec. 26 tsunami that ripped through the low-lying atolls, the Indian government has stood by its long-standing policy of restricting entry to the islands out of concerns for the security of a military air base as well as the protection of indigenous tribes.

"This closed-door approach of not allowing NGOs [non-governmental organizations] is delaying relief efforts," said Shaheen Nilofer, program manager for Eastern India for international aid agency Oxfam (search).

"Valuable time has been lost because of this delay. [India is] accelerating the miseries of the poor people," she said. "Somewhere, someone has to be responsible. If you don't take care of the survivors, the number of deaths can far outnumber the deaths from the tsunami."

By Monday morning, the Home Ministry put India's official death toll at 9,479, with another 5,681 people missing and feared dead in the remote island territories.

Ronen Sen, India's ambassador to the United States, said on Sunday in Washington that "the likelihood of these people remaining alive is diminishing."

"Fifteen thousand is what — unfortunately, that will be the number, yes," Sen told CNN in an interview.

The latest quake to hit Andaman and Nicobar was a 6.0-magnitude tremor that struck overnight Sunday in the seas near the islands, but there were no reports of casualties or other damage, an official at New Delhi's Meteorology Department said on condition of anonymity.

Meanwhile, the handful of Indian volunteer groups and government officials allowed access to the islands continued to conduct an island-by-island search for thousands of missing, feared buried under layers of debris and mud in the 500-plus-island archipelago.

The government said late last week it has not made a decision regarding requests by foreign aid groups, including Medecins Sans Frontieres (search) and Oxfam, to deliver aid to the more remote islands.

Instead, it has ferried survivors to the capital, Port Blair, where entry is not restricted.

Oxfam was the first of several international aid groups to reach Port Blair, where hundreds of survivors have been pouring into camps after being evacuated by ship from far away islands such as Hut Bay, also known as little Andaman. Aid officials said survivors still on the islands were in need of food and water.

"Relief should have reached the doorsteps of the people, and it was possible to do so rather than shunting them all here," said Oxfam's Nilofer, who said the camps were being run in a haphazard way.

"The whole issue is one of trauma, care and support, not just providing food and shelter. People in distress deserve to be treated with dignity. They didn't even have the opportunity to mourn their dead. They were just evacuated and thrown into relief camps," she said.

Meanwhile, hundreds of local fishermen held protests outside of the local fishery office after local radio broadcasts saying they would not be allowed to go out to sea or sell fish because of fears that the fish had been feeding on the dead.

A few men even climbed over the walls and others confronted local officials before police came and dispersed the crowd.

Sorada Madhav Rao, 55, president of the Fishermen's Welfare Association (search), said there are more than 30,000 fishermen in the islands — all of them affected by the tsunami, either directly or indirectly.

"We can't even sell fish that we caught before the earthquake. How do we pay our house rent or pay for our children's education? We weren't given any grain or money. At least give us something to eat," he said.