A Russian passenger jet with at least 44 people on board--including embassy officials--went missing on Wednesday during a demonstration flight in Indonesia, according to reports from the region.

The civilian Sukhoi Superjet 100 "disappeared from radar screens during a flight from Jakarta meant to last 30 minutes," BBC News said.

According to CNN, the aircraft went missing at about 2 p.m. local time. Pilots requested permission to descend from 10,000 feet to 6,000 feet, but air traffic controllers lost radio contact. "The plane began making its descent but vanished from radar screens at 6,200 feet in a mountainous area," CNN reported.

The plane was carrying Indonesia businessmen and Russian embassy officials, Reuters reported. (There were conflicting reports of the exact number of people on board. Reuters said 46, the BBC and CNN said 44.)

The demonstration flight--the second of the day--was part of a tour of six Asian countries. The Superjet 100 was the first commercial airliner produced by Sukhoi, a military plane manufacturer. The mid-size jet can carry up to 103 people. Sukhoi plans to produce 1,000 superjets.

Rescuers at the wreckage of a Russian Sukhoi Superjet plane that crashed into mountains in Indonesia on Wednesday say they have found no sign of survivors.

The Sukhoi Superjet 100 vanished from radar screens 50 minutes after taking off from Jakarta for a brief demonstration flight.

On Thursday a helicopter found debris on the side of a cliff near a dormant volcano.

The spokesman for the rescue effort said a number of bodies had been found.

"So far we haven't found any survivors, but we are still searching," Gagah Prakoso said.

About 45 people are said to have been on board the aircraft.

It crashed into Mount Salak "around 1.5km [one mile] from the spot where the plane last made contact", Indonesian President Susilo Bambang Yudhoyono said on television earlier in the day.

"An investigation must be carried out immediately and thoroughly. Search and rescue operations must prioritise finding any survivors."

Eight Russian pilots and technicians, Indonesian airline representatives and journalists were among those said to be on board the plane.

Earlier reports had said 50 people were on board, but Indonesian agents of the Russian-made plane told the BBC this figure had been revised down because some people got off before take-off.

Sales tour

Aerial searches for the plane on Wednesday were hampered by darkness and strong winds. Fog early on Thursday also delayed search efforts.

The plane took off from east Jakarta's Halim Perdanakusuma airport at 14:00 (07:00 GMT) on Wednesday, on its second flight of the day.

At 14:50, it was recorded as dropping from 10,000ft (3,000m) to 6,000ft near Salak, a peak measuring 7,200ft (2,200m).

Juanda, a villager who lives near the mountain, told local TV: "I saw a big plane passing just over my house."

Rescue teams on the ground were working to reach the site where the debris was spotted, officials said.

Sukhoi officials have been on an Asia-wide tour in recent months to show off their aircraft to airline firms.

The Superjet, a mid-range airliner that can carry up to 100 people, is military plane-maker Sukhoi's first commercial aviation plane.

It was created by a joint venture, majority-owned by Sukhoi, with Italy's Finmeccanica and a number of other foreign and Russian firms also involved.

Sukhoi aimed to sell 42 of its planes to Indonesia, which has witnessed a fast-expanding aviation market to cater for a growing middle class in the world's fourth most populous nation, Reuters adds.

Sukhoi is primarily a military fighter jet manufacturer like the famous SU-27 Flanker (which in often called a near match to American F-15).

Probably some geniuses thought that they could do Cobra Manuvers with a jet airliner like they can with SU-27 fighter jet.