As fighting sporadically erupted in east Ukraine, four Ukrainian servicemen have been killed, a regional Ukrainian chief in the east said on Tuesday.
Gennady Moskal, governor of Luhansk region, claimed that the separatists opened fire on Kiev government forces with mortar and artillery near the village of Katerinovka.
"According to preliminary data, four Ukrainian servicemen have been killed and two others have been wounded, one of them seriously," Moskal said on his Facebook account.
However, the Kiev military forces have yet to confirm the assault made by the separatist militias in the east.
Ukrainian authorities said at the weekend two Russian citizens were captured in the conflict zone where they believed the signs of direct Russian involvement into the east’s separatist war seen on behalf of Donetsk and Luhansk.
But the Kremlin immediately refused on Monday that the two captives could not prove Russia’s intervention by reiterating Moscow’s abiding by the truce signed in Minsk.
The ceasefire which calls the belligerents in eastern Ukraine to terminate hot conflicts and pull out their heavy artillery from the fronts in Luhansk and Donetsk, was sealed in the Belarussian capital Minsk in February.
The Minsk ceasefire agreement has calmed down the situation between the belligerents even if the fragile peace was violated by both Kiev and pro-Russian separatists in Donetsk, Luhansk and Mariupol.
Russia denies its support and involvement for the separatist forces in the Donbass region where ethnically Russian-speaking majority declared self-proclaimed Donetsk and Luhansk People’s republics.
The Ukrainian leadership still suspects that whether Moscow abides by the agreed armistice in Minsk since sporadic violations have recently increased again in the east of the country.
In the wake of the separatist civil war, Ukrainian President Petro Poroshenko has repeatedly voiced his country’s membership aspiration in the NATO alliance and said in April he would present such decision to a nation-wide referendum.
Poroshenko reiterated last week that his country’s membership in the Euro-Atlantic Alliance must be incorporated to the national security document during a National Security and Defence Council meeting in Kiev.
The separatist war in Ukraine caused the death of at least 6,100 people according to UN figures to which Poroshenko had essentially objected as he said the death toll reached at 7000 people during the one year of conflict erupted last year’s March.