Rescuers were searching for 40 missing Indonesians, including women and children, yesterday after a boat carrying them home to celebrate the end of the Islamic fasting month of Ramadan sank off Malaysia.
Two ships, four speedboats and two helicopters were dispatched to scour the seas off Malaysia's southern Johor state but were unable to spot any of those missing, said Amran Daud, an official with the Malaysian Maritime Enforcement Agency (MMEA).
The boat, thought to be carrying 44 passengers, sank in heavy seas on Thursday night around 24 kilometres off the coast, he said, adding four people were rescued on Friday.
"The accident happened two days ago, so we are trying our best," Amran said. "But chances [of finding more survivors] are slim."
It is thought the Indonesians chose to travel by boat because they were working illegally in Malaysia and wished to bypass border controls on their trip home.
The boat sank roughly three hours into its journey from Tanjung Sedili on the state's east coast to Indonesia's Batam Island, with its passengers hoping to return for the Muslim holiday, Amran said.
Fishermen found three of the survivors clinging onto a plastic drum in the water and alerted the authorities, who spotted the fourth man. None of the men, aged between 26 and 31, were wearing life jackets.
"Only four of those on board were rescued by fishermen and MMEA after floating 15 hours in the sea," Amran said.
He added authorities were still investigating what caused the boat to sink.
Shipping accidents off Malaysia's coast are common as thousands from regional neighbours like Indonesia and Myanmar risk journeys in flimsy boats to work illegally in the more affluent country.
Many Indonesians try to leave the country during Ramadan to return home to celebrate Eid al-Fitr with their families. The holiday begins on Thursday.
Authorities said last month they were beefing up patrols to prevent illegal immigrants travelling across the water separating Malaysia and Indonesia.
The Indonesian consulate in Johor was quoted by national news agency Bernama as offering help to illegal immigrants who want to return, saying they could get temporary travel documents and even funds, and urging them not to risk a boat ride.
Malaysia is also a transit point for asylum seekers fleeing unrest in their home countries, such as Myanmar. Many of them sneak into Malaysia via boat or land and then try to reach Australia in boats via Indonesia.
Australia announced a new policy last month to send asylum seekers to Papua New Guinea in order to discourage such journeys after a record number of boatpeople arrived this year - more than 17,300.
Yesterday, Nauru became the second Pacific island nation to agree to settle refugees who try to reach Australia by boat.