PORT BLAIR, India — Waving a flag made of his clothes, a tsunami victim dressed only in his underwear was rescued after surviving alone for 25 days on a flattened island in India’s Andaman and Nicobar archipelago, authorities said Saturday.

The tale of survival reached Port Blair, the archipelago’s capital, on Saturday as authorities slowly restored communication links with faraway islands.

A total of 1,899 people were declared dead across the Andaman and Nicobar islands following the Dec. 26 tsunami, and at least 5,553 remain missing.

Hope has run out for most of the missing. But on Saturday, officials on Campbell Bay island reported that a Nicobarese man named Michael Mangal was spotted on deserted Pillow Panja island on Wednesday, wearing underwear and waving a cloth made from the rest of his clothes.

Mangal was sucked into the sea when the first tsunami wave retreated, but an even bigger second wave dumped him back on the shore. However, he found that no one else had survived from his village, a local government statement said.

Injured and desperate, he survived for the next 25 days only on coconuts before being rescued, it said.