In its daily briefing, the ministry said an Iskander missile had hit a military train on Wednesday at the station of Chaplyne that had been set to deliver arms to Ukrainian forces on the frontline in the eastern Donbas region.

Ukrainian presidential aide Kyrylo Tymoshenko said 21 people were killed when the strike hit the railway station and set five train carriages ablaze, while a boy died when a missile hit his home in the vicinity. The death toll rose to 25 on Thursday after three more bodies were retrieved from rubble, he said.

The Russian ministry said some 200 Ukrainian military personnel had died in the attack.

Reuters was unable to independently verify the reports.