Ukrainian law enforcers have demanded that members of illegal armed formations immediately release the children who are held captive by militants in eastern Ukraine.

"I want to appeal to those who currently hold our children as hostages... These shameful actions are not just inhumane, these are the actions of obscurants and godless people," the Ukrainian interior minister's adviser, Zorian Shkiriak, said at a briefing in Kyiv on Thursday.

He said: "We are demanding the immediate release of our children. These are Ukrainian children, and the state wants and will worry about them. We are waiting for them and demanding their immediate return."

On Thursday, the Ukrainian president's representative on the settlement of the situation in the Donetsk and Luhansk regions, Iryna Heraschenko, said that members of illegal armed groups in the east of the country were holding more than 200 hostages.