The U.N. peacekeeping mission in the DRC, known by its French initials MONUSCO, said it worked alongside the Congolese military to fend off recent attacks from the rebel March 23 Movement.
M23 briefly seized control of Goma, the provincial capital of North Kivu province, last year. It's suspected of committing crimes against humanity.
MONUSCO said three civilians were killed and three peacekeepers were injured by mortar shells fired from M23 positions during recent fighting near Goma.
Martin Kobler, U.N. special envoy for DRC, told German broadcaster Deutsche Welle the local population was rallying against peacekeepers because they were frustrated with the security situation.
A special MONUSCO unit is authorized to use force in DRC. Critics of the brigade said it would make an already tense security situation worse.
Kobler stressed in an interview published Tuesday the peacekeepers were working for, not against, the civilian population in DRC.
"We as United Nations are not the magic solution to the problems of Congo, but we do everything in our power to assist the government in order to solve their problems," he said.
MONUSCO estimates more than 1 million civilians are living as refugees in eastern DRC.
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