Ukraine says four of its soldiers have been killed and 18 wounded in fighting against pro-Russian separatists over the past 24 hours.
The military said on November 13 that the fighting was concentrated in the area of the international airport outside Donetsk, one of two rebel-held provincial capitals in eastern Ukraine, and the village of Debaltseve near the border with Luhansk province.
Rebel authorities said three people were injured by artillery shelling in Donestk overnight.
The reports come after the UN Security Council held an emergency session at the behest of the United States but took no action despite what a top UN official said was the possibility of a "return to full-scale fighting" in eastern Ukraine.
NATO said on November 12 that “multiple columns” of Russian tanks, artillery, and antiaircraft units had crossed from Russia into separatist-controlled territory over the previous two days -- an allegation denied by Moscow.
International monitors say they have seen unmarked military forces bolstering separatist positions.
The conflict, which has killed more than 4,000 people since April, persists despite a September 5 cease-fire.