Image copyright AP Image caption Wreckage was spotted after an aerial search of the area where the plane lost contact

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.

Image copyright AP Image caption Relatives - including 10-year-old Tasya Kamagi, whose father was on board - gathered at Jakarta airport to await news of their loved ones. In pictures: Indonesia plane crash

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.