"About 10 p.m. on July 25, State Border Service officers at the Berezovoye checkpoint detained a KAMAZ vehicle fully packed with ammunition. The vehicle was accompanied by two persons in uniform," the service said.
It added that the border guards "found that one of the men was a professional soldier of the Russian Armed Forces with the rank of Major," while the other was allegedly a man fighting for the Donetsk Region's independence.
"The law enforcement officers discovered a large number of boxes of ammunition of various calibers in the KAMAZ," the State Border Service said.
According to the border guards, the truck was on its way to the Russian-Ukrainian border when it was detained; the vehicle reportedly came from the territory currently controlled by Donetsk Region independence supporters.
Officers from Ukraine's Security Service and Interior Ministry, as well as other government agencies, arrived on the scene to clarify all the circumstances.
The Ukrainian authorities, the United States and the European Union have repeatedly accused Moscow of interfering in Ukraine's domestic affairs.
For his part, Russian Foreign Minister Sergei Lavrov said that allegations regarding the presence of Russian servicemen in the Donbass Region in eastern Ukraine have never been confirmed with concrete facts.