Two-hundred pro-Russian separatists — 10 of them female — took an oath to the Donetsk People's Republic on Sunday, the 73rd anniversary of the start of the Great Patriotic War, Interfax reported.
The ceremony opened with a moment of silence for the pro-Russian separatists who were killed in recent battles with Ukrainian troops.
Last week, Ukrainian authorities said about 300 pro-Russian separatists had been killed as the Kiev government struggled to reassert control in the predominantly Russian-speaking east.
At Sunday's ceremony, portraits of the dead were set up around the city's monument to Vladimir Lenin, where mourners placed carnations as a makeshift memorial.
The self-proclaimed leader of Novorossia, Pavel Gubarev, was also present to congratulate the 200 new fighters, who were later due to head to Slovyansk.
A major separatist stronghold, Slovyansk has seen some of the most intense fighting between Ukrainian troops and pro-Russian rebels this month.