Prime Minister Manmohan Singh today expressed shock over the boat tragedy in the Andaman and Nicobar Islands and condoled the loss of lives.
Singh asked all central agencies to immediately assist in the rescue and relief operations, a PMO statement said.
At least 21 persons died when the tourist boat carrying them capsized in the Bay of Bengal, official sources said in Port Blair.
The boat carrying 45 people sank on its way from Ross Island to North Bay.
