Indonesian searchers with body bags and hoists scaled a steep volcano Friday to retrieve at least 45 bodies spread over the jungly terrain where a Russian jet crashed during a sales flight.

The crews were using climbing equipment to ascend the near-vertical face of Mount Salak, a dormant volcano south of Jakarta, and were believed to be about 200 metres (650 feet) from reaching the first bodies, authorities said.

All aboard the Sukhoi Superjet 100 were killed, authorities said Thursday, a day after the plane slammed into the mountain during a flight that was meant to spur international sales of Russia's first post-Soviet civilian jet.

The military commander of the mission said that one team was climbing up from the foot of the mountain, while another was going down from the top.

The difficult terrain over the dormant volcano, which juts more than 7,200 feet (2,200 metres) into the air and is most days shrouded in thick fog, has been an extreme challenge to the searchers.

The mist had stopped helicopters from getting close to the area, since a chopper pilot first spotted the wreckage Thursday morning, authorities said.

"The plane crashed into the mountain and slid 250 metres down, to 1,800 metres," said the commander, Colonel Anton Mukti Putranto.

The twin-engine Superjet Wednesday descended to 6,000 feet (1,800 metres) before vanishing from radar screens, 50 minutes into what was meant to be a short flight to show off its capabilities to prospective airline buyers.

"There is so far no information about (the number of) victims. They could see only the debris of the plane because it's still quite a distance from where they are," Putranto said, referring to the team closest to the site.

Ketut Parwa, search and rescue agency chief for the capital Jakarta, said victims would be placed into body bags, hoisted up the mountain, then carried to ambulances a long distance away on foot.

He said helicopters would then fly the bodies to the capital's Halim Perdanakusuma military airport, where authorities have set up a forensics post to identify victims through DNA samples taken from relatives.

The company representing Sukhoi in Indonesia, Trimarga Rekatama, originally said 50 passengers were on board but Thursday revised the number to 45. Local rescue officials said the plane was carrying 46 people.

Those aboard were mostly Indonesian aviation representatives, but there were also eight Russians -- four of them crew and four Sukhoi employees -- plus an American and a Frenchman, officials said.

The demonstration flight was part of an Asian tour to promote the aircraft, a joint venture between Sukhoi and Italy's Alenia Aeronautica, which made its first commercial flight last year.

In Russia, investigators on Thursday opened a criminal probe into possible misconduct during preparations for the flight.

An investigative committee said it would look at "the procedure for preparing the flight crew and also the technical condition of the craft itself before its departure from Russia".

The captain, 57-year-old Alexander Yablontsev, was a veteran pilot.

The loss of the new Superjet is a heavy blow to the Russian aviation industry, which was hoping that the country's most advanced civilian jet would improve its image.

But Sukhoi's agent in Jakarta said there was no talk of suspending sales in Indonesia, Southeast Asia's largest economy and an archipelago of more than 17,000 islands where air travel and airlines are booming.

"There is no suspension on Sukhoi purchases at the moment," said Sunaryo, a spokesman for Trimarga Rekatama, who goes by one name.