Ukrainian regional governor Maksym Kozytskyy said 35 people were killed and 134 wounded in the attack on the Yavoriv training base, near a major crossing point into Poland used by refugees from the conflict.
Russia said it had attacked the facility, adding the strike had killed "up to 180 foreign mercenaries" and destroyed a large amount of weapons supplied by outside nations.
Defence ministry spokesperson Igor Konashenkov told a briefing that Russia would continue its attacks against what he called foreign mercenaries.
