Aircraft from Singapore yesterday joined Indonesia?s intensive search for a plane that disappeared in bad weather with 102 people aboard four days ago.

Military and civilian aircraft have been scouring the jungles and rugged mountains of western Sulawesi while navy vessels combed the Makassar Strait between the islands of Sulawesi and Borneo.

But heavy rains and strong winds have hampered the search effort and the rough terrain has made communication and transport difficult.

Senior government officials have apologised for erroneously saying the 17-year-old Boeing 737-400, operated by budget carrier Adam Air, had been spotted on Sulawesi and 12 passengers had survived.

The missing plane was carrying 96 passengers and six crew. A copy of its manifest showed three passengers as non-Indonesians. The US embassy in Jakarta said they were Americans.

Tough conditions

Two Singaporean Fokker-50s have joined Indonesian military aircraft in the search, while three ships have joined the effort and another is on they way, First Air Marshal Eddy Suyanto, commander of the airbase in Makassar, told Reuters.

Officials had announced late on Wednesday that the United States was also offering unspecified aid.

?The more people who look for (the plane), hopefully the faster we find it,? Air Force Lieutenant Colonel Firdaus Syamsudin told Reuters.

South Sulawesi governor Amin Syam said on Wednesday many rescuers were worn out following Tuesday?s false alert. Officials said the mistaken information about the crash site and survivors came from accounts from a village that police then relayed to government agencies.

The circulation of the report drew strong criticism from politicians and passengers? relatives. ?I feel fooled. This is what I call playing games with the feelings of the victims? relatives,? said Peter Tolitton, whose brother was aboard the plane. ?If up to the ministerial level the information is inaccurate, we doubt the credibility of the officials.?

The confusion over the missing plane highlighted the logistical difficulties of dealing with disasters, from quakes and volcanoes to floods and forest fires, in an archipelago of 17,000 islands that stretches about as wide as the United States.

President Susilo Bambang Yudhoyono has ordered a full investigation into the condition of all commercial planes in Indonesia and what went wrong in the Adam Air case, as well as an evaluation of the nation?s transportation system.

Adam Air?s plane disappeared less than three days after a ferry capsized and sank off Indonesia?s main island of Java. Officials say at least 239 of those on the ferry have been rescued since it sank overnight Friday, but nearly 400 more are unaccounted for. Twelve survivors, who beached near an offshore rig, including a man called Wiratno who claimed to be the ferry?s captain, were rescued on Wednesday, the Indonesian navy said.

The navy?s Eastern Fleet spokesman Tony Syaiful told reporters the professed captain reportedly tried to commit suicide and is being investigated. Ferries are ubiquitous in Indonesia as an inexpensive way to travel among its many islands, while air travel has mushroomed since the industry was liberalised in the late 1990s, enabling privately owned budget airlines to operate.

Ahmad PATHONI