Jakarta, Indonesia (CNN) -- The wreckage of a Russian passenger airliner that went missing during a demonstration flight over Indonesia has been located in a mountainous area, a local official said Thursday.
Teams searching for the plane spotted debris from the Sukhoi Superjet 100 at a height of about 5,800 feet (1,800 meters) on the side of Mount Salak, a volcano south of Jakarta, said Daryatmo, head of the National Search and Rescue Agency.
Daryatmo, who like many Indonesians only uses one name, said the Sukhoi logo had been identified amid the wreckage.
No information was immediately available about the passengers who were on board the plane, which disappeared off radar screens on Wednesday.
Rescue workers on the ground have not yet been able to reach the wreckage, but the Search and Rescue Agency is dispatching a helicopter to the site, Daryatmo said.
President Susilo Bambang Yudhoyono of Indonesia said in a brief televised address that the Russian plane appeared to have crashed into Mount Salak.
An image released by the Indonesian military showed bits of debris strewn across a patch of steep mountainside stripped bare of the thick vegetation covering the surrounding area.
The cause of the crash remained unclear.
There were conflicting reports about the number of people on the Sukhoi jet, Russia's newest civilian airliner, when it went down. The confusion seemed to stem from uncertainty about whether everybody on the passenger list actually boarded the plane.
Map: Russian jet crash
The latest estimate of the number of people on board is 45, according to Sunaryo, an official with Sukhoi's Indonesian agent, Trimarga Rekatama.
That figure includes the eight Russian crew members as well as a number of journalists and aviation industry officials.
Contact lost with plane minutes into flight
The plane was on its second demonstration flight Wednesday when it lost contact with air controllers at Jakarta's Halim Perdanakusuma Airport.
"The first demonstration flight in the morning went smoothly," said Sunaryo, who also uses only one name. "There were no problems."
On the second flight, the plane began making its descent but vanished from radar screens at 6,200 feet in a mountainous area.
The plane lost contact with air traffic controllers at 2:12 p.m., 21 minutes after taking off, said Marsda Daryatmo, head of the search and rescue agency. Two helicopters were immediately sent out to search for the plane but had to return to their bases due to strong winds and unpredictable weather.
The Sukhoi jet arrived in Jakarta as part of a demonstration tour of six Asian countries. It had been to Myanmar, Pakistan and Kazakhstan, and was due to visit Laos and Vietnam after Indonesia, said the Russian news agency RIA Novosti.
Sukhoi manufactures military aircraft and is known especially for its fighter jets. Its civilian aircraft is narrow-bodied with a dual-class cabin that can transport 100 passengers over regional routes. It flew its maiden flight in 2008.
In March, a Superjet 100 operated by Russia's Aeroflot Airlines was forced to abandon its flight to Astrakhan, Russia, and return to Moscow because of problems with the undercarriage, according to RIA Novosti.
A similar defect in another Aeroflot-operated Superjet 100 plane had to be fixed in Minsk in December.
Russia's state-run United Aircraft Corp. said the defect did not affect passenger safety.