The Indonesian passenger plane that crashed with 54 people on board in Indonesia's mountainous Papua region was transporting about 6.5 billion rupiah ($470,000) in cash to distribute to poor families in the eastern province.
"Four of our personnel were escorting the funds," said Haryono, the head of Jayapura post office. "The money was in four bags", he added.
Rescue teams have spotted the wreckage of the plane in the Papua region.
There has been no information of any survivors from the crash, which happened in bad weather on Sunday. Transportation Ministry spokesman Julius Barata said there was no indication that the pilot had made a distress call.
Rescuers head to suspected Indonesian plane crash site in Papua
Officials said the wreckage was spotted about 12 kilometers (7 miles) from Oksibil, and Henry Bambang Soelistyo, the chief of the National Search and Rescue Agency, said search and rescue teams were preparing to try to reach the crash site by air and foot.
The ATR42-300 twin turboprop plane was carrying 49 passengers and five crew members on a scheduled 42-minute journey, Barata said. Five children, including two infants, were among the passengers.
The plane operated by Indonesian carrier Trigana Air lost contact with air traffic control just before 3pm (0600 GMT) Sunday after taking off from Jayapura, the capital of Papua province, the search and rescue agency said.
The ATR 42-300 twin-turboprop plane was carrying 44 adult passengers, five children and five crew on the flight which was scheduled to take about 45 minutes, it said.
But the plane disappeared about 10 minutes before reaching its destination Oksibil, a remote settlement in the mountains south of Jayapura, shortly after it asked permission to start descending to land.
Officials said initially that villagers in the Okbape district of Papua reported seeing a plane crash. The transport ministry later said local residents had found the wreckage.
"The plane has been found (by villagers). According to residents, the flight had crashed into a mountain," said the transport ministry's director-general of air transportation, Suprasetyo, who goes by one name.
Officials were still verifying the information from local residents, he said. There was no information about whether anyone may have survived.
Search and rescue teams, police and the military would head to the site as soon as possible Monday, said transport ministry spokesman JA Barata.
'Dark and cloudy'
After the plane failed to land, Trigana Air sent another flight over the area to hunt for it but the aircraft failed to spot anything due to bad weather.
Captain Beni Sumaryanto, Trigana Air's service director of operations, told AFP that Oksibil was "a mountainous area where the weather is very unpredictable. It can suddenly turn foggy, dark and windy without warning.
"We strongly suspect it's a weather issue. It is not overcapacity, as the plane could take 50 passengers." Barata said the weather in the area had been "very dark and cloudy".
Much of Papua is covered with impenetrable jungles and mountains. Some planes that have crashed in the past have never been found. Oksibil, which is 280 kilometers (175 miles) south of Jayapura, was experiencing heavy rain, strong winds and fog when the plane lost contact with the airport minutes before it was scheduled to land, said Susanto, the head of Papua's search and rescue agency.
Dudi Sudibyo, an aviation analyst, said that Papua is a particularly dangerous place to fly because of its mountainous terrain and rapidly changing weather patterns. "I can say that a pilot who is capable of flying there will be able to fly an aircraft in any part of the world," he said.
European plane maker ATR said in a statement on Sunday that it "acknowledges the reported loss of contact" with the Trigana flight "and is standing by to support the relevant aviation authorities."
Trigana Air is a small airline established in 1991 that operates domestic services to around 40 destinations in Indonesia. It has suffered 14 serious incidents since it began operations, according to the Aviation Safety Network, which monitors air accidents.
The airline is on a blacklist of carriers banned from European Union airspace.
Indonesia has a patchy aviation safety record. In December an AirAsia plane flying from the Indonesian city of Surabaya to Singapore crashed in the Java Sea during stormy weather, killing all 162 people on board.
In June an Indonesian military plane crashed into a residential neighbourhood in the city of Medan, exploding in a fireball and killing 142 people.
The aviation sector in Indonesia is expanding fast as the economy booms but airlines are struggling to find enough well-trained personnel to keep up with the rapid growth.
With inputs from AP, AFP