Tehran, Dec 25, IRNA - The Russian aircraft TU-154, which had disappeared from radar shortly after take off in Sochi Sunday, has crashed in the mountains in Krasnodar Territory in the south of the country, a source in local security services told RIA Novosti Sunday.

The Russian media reports quoted the source as saying the RIA Novosti that the plane with 91 people aboard, including 83 passengers and eight crew members, lost contact with land while flying over the Black Sea.

Journalists, military personnel, musicians from an official army choir of the Russian armed forces, were also onboard.

'According to preliminary findings, the missing TU-154 arrived in Sochi from Chkalovsky airport in Moscow region for refueling,' the Russia media reported.

Most likely, it crashed in the mountainous area of Krasnodar Territory,' the source told RIA Novosti.

The preliminary data shows that the disappeared plane was heading to Syria's Hmeimim airbase.

According to the source, the possible reasons for the crash could be technical malfunction or pilot error.

The source added that the plane disappeared from radars 20 minutes after departing from Sochi, Krasnodar Krai.