Soldiers targeting the Kamwina Nsapu militia group in central Democratic Republic of Congo killed at least 101 people between Feb. 9 and Feb. 13, including 39 women, the U.N. said on Tuesday.

The soldiers fired indiscriminately with machine guns when they saw the militia fighters, who were armed mainly with machetes and spears, human rights spokeswoman Liz Throssell said, citing sources in the country.

"We are deeply concerned at the reported high number of deaths, which if confirmed would suggest excessive and disproportionate use of force by the soldiers," she said.

Hundreds have died and tens of thousands have been uprooted in central Congo in recent months in battles between security forces and the militia, who are seeking to avenge the death of their leader Kamwina Nsapu.

He was killed by the Congolese armed forces last August, after vowing to rid Congo's Kasai-Central province of all state security forces, accusing them of abusing the local population.

"It appears that since then the militia have become radicalized and they are attacking state institutions, what they see as the symbols of the state. The actual roots of the conflict are very deep and very complex," Throssell said.

The authority of some customary chiefs is recognized by the government and can be passed from father to son, but Kamwina Nsapu was not officially recognized.