KIEV, Feb. 20 (Xinhua) -- Ukrainian military spokesman Vladislav Seleznyov said here Friday that at least 110 Ukrainian troops are being held captive by pro-independence rebels in eastern Ukraine, while 31 soldiers are still missing.

"Now we are working to establish the whereabouts of our troops," Seleznyov told reporters during a media briefing.

The representatives of the Organization for Security and Cooperation in Europe (OSCE) monitoring mission, as well as several governmental and non-governmental organizations are assisting Ukraine in searching for the missing soldiers, Seleznyov added.

Over the past 24 hours, two Ukrainian servicemen were killed and three others wounded in clashes with rebels, he said.

Earlier in the day, the self-styled rebel ombudsman for human rights, Daria Morozova told local media that a fresh round of war prisoner exchange between the government and the insurgent forces will start Saturday.

There was no immediate confirmation of the possible swap from the Ukrainian authorities.

The warring sides have undertaken a commitment to release all hostages based on the principle of "all for all" under the framework of a peace agreement reached in Minsk, capital of Belarus, on Feb. 12. Enditem