Ten cars of cargo train derailed on Friday after bombing by unidentified men in the North Caucasian republic of Dagestan, the Itar-Tass news agency reported.
The incident occurred at 05:10 Moscow time (0110 GMT) on the 2,321-km-long Manas-Achi rail track, the Itar-Tass quoted the local railway department as saying.
The department said the incident which derailed the Derbent-bound train was a result of a sabotage.
An investigation is underway. The authorities are also taking measures to restore the interrupted railway traffic.