Basurin, the insurgents’ military commander in the Donetsk administrative region of eastern Ukraine, said that of the 10,000 Ukrainian soldiers deployed in Devaltseve by the authorities in Kiev, approximately 3,000 have been killed in action.

In case the casualty figures are confirmed, it would be the greatest loss suffered by the Ukrainian troops since fighting broke out last April between troops loyal to the Kiev government and pro-Russian separatists in Donetsk and Luhansk.

Not including the 3,000 casualties claimed by Basurin or the nearly 300 victims on a Malaysian passenger plane apparently shot down by mistake by one of the warring parties, at least 5,500 people have died in eastern Ukraine since separatist tensions erupted in violence last April.

According to Ukrainian sources, a column of troops loyal to the Kiev government was attacked on Wednesday by tanks manned by the pro-Russian rebels when the Ukrainian brigade was on its way out of Devaltseve, a strategic crossroads between Donetsk and Luhansk.

Basurin was speaking shortly after Kiev ordered its troops to withdraw from Devaltseve, which has been under constant attack by the separatists in recent weeks in fighting that continued unabated after last week’s signing of a cease-fire accord in Minsk.

Speaking from Kiev airport before heading to the frontlines, Ukrainian President Petro Poroshenko confirmed that he gave the order for government’ troops to redeploy from Devaltseve.

According to Poroshenko, Ukrainian units left in an orderly manner, with all their weaponry, tanks, armored vehicles and artillery pieces, which would mean that Ukrainian troops were not encircled and cut off from their supply route by the separatists.

But the insurgents insisted Ukrainian forces retreated from the besieged city after they pledged to lay down their weapons, as separatist militias secured an open corridor for their exit from the city.