One Belarusian and two Italian journalists were stopped Monday by gunmen as they reported in the city of Slovyansk, which has been occupied by pro-Russia forces for more than a week.
Slovyansk is one of many cities in Ukraine's Russian-speaking eastern region where insurgents are demanding greater ties with Russia.
Dmitry Galko told The Associated Press that he and two Italian colleagues were taken in then freed some time later after a document check.
Ukraine's Foreign Ministry and the Organisation for Security and Cooperation in Europe, a 57-nation group that includes Russia and the United States, condemned the detentions and demanded the journalists' immediate release.