Local activists accused the police and soldiers of opening fire as the refugees protested over the plan in the town of Kamanyola in eastern Democratic Republic of Congo on Friday.
AT LEAST 36 Burundi refugees, 15 of them women, have been killed in clashes with the Congolese military, a United Nations official said at the weekend.
The Special Representative of the UN Secretary-General Congo, Maman Sidikou, in a statement said that he condemned the acts of violence perpetrated in Kamanyola.
A Burundian refugee told AFP news agency: "I saw people falling down, men, ..."
Congo's government says it is opening an investigation to establish the facts and true identity of the "supposed refugees", spokesman Lambert Mende said.
Boji said troops tried to disperse the refugees by "firing in the air but were overwhelmed" when the group responded by throwing stones.
Eyewitness Alfred Rukungo said the soldiers continued shooting into the crowd even after some refugees were wounded.
The Congolese government, the U.N refugee agency and the U.N. peacekeeping mission in Congo "have deployed teams on site to shed light on everything that happened", said the coordinator of the U.N. Communications Group in Congo, Florence Marchal.
About 44 000 Burundian refugees live in DRC, which coincidentally is beset by militancy after President Joseph Kabila remained at the helm of the Central African country after his mandate elapsed at the end of 2016.
The UN High Commissioner for Refugees (UNHCR) said it was shocked and saddened over the violent deaths.