Merak, Indonesia - Survivors from an asylum-seeker boat that sank off Indonesia pleaded on Friday to go to Australia and described how they had yelled at rescue vessels to save them, but nobody spotted them.

Fifty-four people - mostly males and all believed to be Afghans - were plucked from the ocean after their wooden boat broke up and sank early on Wednesday morning. Some had been languishing in the water for over 24 hours.

The survivors included a young boy who looked around 10.

As they were brought into the Indonesian port of Merak, in western Java, some looked dehydrated and the group at first refused to get off. A few wept hysterically, shouting: “We want to go to Australia!”

They eventually all got off and some took a bus to a hotel, while others were taken by ambulance to hospital.

Australian and Indonesian ships and aircraft were meanwhile scouring the seas for about 100 others Ä including children - still missing.

Survivors said their boat began to leak before strong waves shattered the rickety vessel, which was believed to be about eight nautical miles from the main Indonesian island of Java when it ran into trouble.

“As far as I could tell, everyone was still alive after the boat broke up. We saw Indonesian boats circling around for four or five hours and we kept shouting 'help! help!' but they didn't see us,” Muhammad Ali, 53, told AFP.

“If only they had come, more of us would have been saved.”

The leaking boat sent a distress signal and Indonesia sent out rescue crews, but they abandoned the search after about 10 hours saying they could find no sign of a sunken vessel.

The survivors were later rescued by a cargo ship and an Australian naval vessel, before being transferred onto Indonesian rescue boats.

Muhammad Zahir, 25, said he held on to a large piece of debris and fastened himself to it with rope, which helped him from being swept away by the waves.

“We were shivering and tired, and those who were too tired were taken away by the current. There were also women, young girls and boys,” he said.

Rescuers said hopes of finding the rest of the asylum-seekers were fading fast. The bulk of the survivors were picked up on Thursday evening but there had been no more found since.

“We have a window of opportunity - people can survive in the sea for up to 36, maybe 48 hours,” Australian Home Affairs Minister Jason Clare told reporters.

Indonesian and Australian rescuers said they would not abandon the search.

“The standard search period for us is seven days,” said Gagah Prakoso, a spokesman for Indonesia's National Search and Rescue Agency (Basarnas).

In Australia, the Sydney Morning Herald newspaper reported that the asylum vessel was organised by a 25-year-old Pakistani people-smuggler.

Australian Prime Minister Julia Gillard defended Indonesia's handling of the initial aborted rescue.

“I believe that the Indonesians did the best that they could,” she said.

“This should reinforce the message about how dangerous these journeys are, it's a big ocean, it's a dangerous ocean. We've seen too many people lose their lives trying to make the journey to Australia.”

Australia is facing a steady influx of asylum-seekers arriving by boat, many of whom use Indonesia as a transit hub, paying people-smugglers for passage on wooden vessels after fleeing their home countries.

More than 300 boatpeople have died en route to Australia this year, with vessels being intercepted by the Australian navy on almost a daily basis, including one carrying 31 people late Thursday. - Sapa-AFP