The anti-terrorist operation resumed in eastern Ukraine overnight into Tuesday – the positions of illegal armed groups were hit with artillery fire and airstrikes, spokesman for the operation Oleksiy Dmytrashkovsky said.

"Following the announcement of the Ukrainian president, the counter-terrorism operation came into effect. Artillery opened fire and airstrikes were held at strategic sites of terrorists and their gathering places," Dmytrashkovsky told Interfax-Ukraine on Tuesday.

Self-defense activists taking side of the Ukrainian army were the ones to report locations of illegal armed formations, Dmytrashkovsky said. "So, three people were taken yesterday and now talks are being held with a big group of self-defense activists," he said.

In the past 24 hours one Ukrainian law enforcer died and 17 were injured, Dmytrashkovsky said.

In general, during the ceasefire of Ukrainian law enforcers, which started at 2200 on June 20, separatists carried out 122 attacks on subdivisions of Ukrainian law enforcers, Dmytrashkovsky said.