Moscow says the troops were stationed inside a zinc factory

Russian aircraft have struck a zinc factory in Donbass, killing dozens of Polish fighters, the Russian Defense Ministry said on Saturday.

"Up to 80 Polish mercenaries" were killed, and 20 armored vehicles and eight Grad multiple rocket launchers were destroyed in the town of Konstantinovka, Defense Ministry spokesman, Lieutenant General Igor Konashenkov, said during his daily briefing.

He added that artillery pieces, personnel and drones had been targeted in other areas. Konashenkov said a Tochka-U ballistic missile has been intercepted mid-air near the town of Molodyozhnoye in southern Ukraine.

Numerous fighters from EU member states and countries such as the US and Canada have been fighting for Ukraine.

Earlier this month, a court in the Donetsk People's Republic handed death sentences to two British nationals and one Moroccan, who were serving with the Ukrainian forces. The men have not yet been executed.

Russia attacked its neighboring state in late February, following Ukraine's failure to implement the terms of the Minsk agreements, first signed in 2014, and Moscow's eventual recognition of the Donbass republics of Donetsk and Lugansk. The German- and French-brokered protocol was designed to give the breakaway regions special status within the Ukrainian state.

The Kremlin has since demanded that Ukraine officially declare itself a neutral country that will never join the US-led NATO military bloc. Kiev insists the Russian offensive was completely unprovoked and has denied claims it was planning to retake the two republics by force.

(RT.com)