"There were mortar attacks on roadblocks, support and observation points located in the vicinity of Nikishin, and small arms attacks on a Ukrainian unit near Chernukhin,” the press service of the Anti-Terrorist Operation or ATO – as Kyiv names its counterinsurgency operation – said in a statement.

“Returning fire suppressed the militants’ firing points,” the statement read.

“Our actions forced the terrorists constantly maneuver and change their positions."

The statement also reported that at around midnight militants attacked a Ukrainian anti-tank unit near the village of Berezove in Donetsk region. One Ukrainian soldier was wounded soldier in the attack, and was evacuated to hospital.

The situation in Luhansk region remains tense, with militant sabotage and reconnaissance groups active, and Ukrainian forces being shelled, including in the area of Mariupol. Ukrainian forces continue to defend Donetsk airport, and this strategic facility is still under government control, the ATO headquarters said.

Earlier this week the ​​ATO reported a significant increase in the activities of Russian troops and militants in the Donbas conflict zone, which it said was associated with a delivery of ammunition to the Donbas that Russia made with its "humanitarian" convoys. Russia says its truck convoys only carry aid for civilians.

The Ukrainian military says the most difficult situations in the conflict zone remain those in the areas of Debaltseve and the city of Donetsk.