An airliner with 102 people on board which went missing during bad weather in eastern Indonesia on Monday appeared to have come down near Mamuju, government and company officials said.
Indonesian authorities said a signal from its emergency locator beacon (ELB) indicated the plane was in the western Sulawesi district of Mamuju, about 1,350 km northeast of Jakarta. Rescue workers were to leave for the area early on Tuesday.
The plane, a Boeing 737-400 of the Indonesian private low-cost airline Adam Air, left the East Javan capital Surabaya for Makassar in South Sulawesi and Manado, the provincial capital of North Sulawesi, according to Dodi, an official at the Indonesian national search and rescue agency.
"We have reports that the plane lost contact at about 3 pm," Dodi said, adding that the plane was scheduled to arrive at Manado's Sam Ratulangi airport at 4 pm.
The plane, flight number KI-574, was carrying 96 passengers including seven children and four infants, plus a crew of six, said Dodi, who like many Indonesians uses only one name.
Ichsan Tatang, director-general of air communications at the transport ministry, told reporters preliminary information from a Singaporean satellite as well as from other aircraft in the region said the plane sent out a distress signal in bad weather.
Tatang said the ELB signal indicated the plane was located at Mamuju, about 83 nautical miles northwest of Makassar.
"We will begin search and rescue operation tomorrow (Tuesday) morning," said Edy Suyatno, chief of the air force base in Makassar, adding that a number of aircraft would back up the rescue operation.
Tatang said it was bad weather — heavy rains and strong winds — when the plane lost contact. He added that the plane, with 45,371 flight hours and 26,725 landings, was airworthy.
Transport Minister Hatta Radjasa said the plane has lost contact at an altitude of around 1,000 metres.
"We don't know yet exactly the cause behind the missing plane. The important thing is to immediately conduct a search and efforts to rescue the passengers," Radjasa told Elshinta private radio.
He said he had contacted the head of the Indonesian Armed Forces (TNI) for help, including search aircraft.
"We greatly hope that the plane made an emergency landing," he said. "We prayed to God with the hope that we will be able rescue them immediately."
Adam Air began operations in Indonesia several years ago and most of its flights are domestic.
Last year, one of its aircraft lost all communication and navigation systems for four hours during a flight between Jakarta and Makassar, forcing the pilot to make an emergency landing.