Twenty migrants from Bangladesh and Burma have been found dead from starvation and dehydration on a wooden trawler adrift in the Bay of Bengal.
People regularly attempt to leave Burma by boat
Sri Lanka's navy, which found them, said 71 survivors were rescued from the crowded boat, which had been drifting for two weeks after its engine broke.
They told the sailors that they were trying to get to Thailand or Malaysia.
Correspondents say that the same ocean journey is regularly attempted by boatloads of illegal migrants.
A navy spokesman said that they had been alerted to the vessel's presence by fishermen, and at first had suspected it might be involved in gun running for the Tamil Tiger rebels.
The spokesman said the trawler set sail from Cox's Bazaar in Bangladesh, on its border with Burma, and was on the way to Malaysia or Thailand when its engines failed.
They said the bodies of the dead passengers have been "thrown overboard".
After sailors handed out food, water and gave medical treatment at sea, the boat was taken under tow to the Sri Lanka Navy base at Trincomalee.