No group of members of illegal armed formations has claimed responsibility for the kidnapping of observers of the OSCE's special monitoring mission in Donetsk and Luhansk regions.

"I would like to clearly note that no person or group has claimed responsibility for what is happening," spokesman for the OSCE's special monitoring mission in Ukraine Michael Bociurkiw said at a briefing in Kyiv on Friday.

He noted that the OSCE mission called on those who hold its observers to contact it and on all residents who have any information about the observers to convey it to the mission.

"The situation has not changed. We still were not able to establish direct contact with our two groups," he said.

Bociurkiw said that the mission was working for the early release of its observers and uses "various channels."

Two groups of the mission that monitored the situation in the eastern regions are currently in captivity. The first group of OSCE observers, composed of four people - citizens of Switzerland, Estonia, Turkey and Denmark - disappeared in Donetsk region late on May 26. The second group, also composed of four people, was last in contact late on May 29 at a checkpoint near Severodonetsk, Luhansk region.