"Violence against civilians is unacceptable," Estonian Foreign Minister Urmas Paet said. "We need to do everything possible to protect them," he noted, adding that those fleeing the conflict need to be guaranteed a safe escape route through a humanitarian corridor.

According to a UN report on human rights, civilians trying to escape the conflict zone have been attacked and killed. "Many of them have been prevented from leaving Donetsk and Luhansk by armed groups," Paet said in reference to the human rights report, and added that the population's most vulnerable groups - children from orphanages, the elderly and people with disabilities - are not being evacuated quickly enough.

Paet stated that Russia's immediate withdrawal from Ukraine is necessary to end the violence. "Russia must also stop sending weapons to Ukraine and must join Ukraine in gaining control of the situation at the borders," he added.

The UN report also points out continuing human rights violations by armed gangs. "Abductions and the mistreatment of detainees occur on a daily basis," Paet said. "It is feared that nearly 500 people are currently being detained by various armed groups."

According to the report, Ukrainian authorities have investigated more than 1500 crimes and over 150 people have been indicted.

"The Ukrainian government must act resolutely to do everything in their power to prevent all attempts at retaliation and other unlawful acts of punishment," Paet emphasised.