The shells with a reported caliber of 120 millimeters were found on Monday by local farmers in a field one kilometer off a small village belonging to the settlement of Yekaterinovsky, the source said.
The territory where the ammunition was found has been cordoned off. The local administration has asked for help to render the shells safe.
It is not the first incident when Ukrainian ammunition was found on the Russian territory. In a previous incident a Ukrainian shell was found also in the Matveyev-Kurgan district on September 23.