In a statement Friday, she calls on all parties in the country to respect human rights and international humanitarian law.
She says that during previous outbreaks of fighting in the region, there have been "horrendous large-scale summary and arbitrary executions, rapes, disappearances, torture, harassment as well as unlawful and arbitrary detention.
Spokesman Rupert Colville says that over the past few days UN human rights staff in the region have recorded a number of fresh violations of human rights.
"In the provincial capital of Goma lootings, killings and rapes, appear to have been carried out primarily by renegade soldiers belonging to the national army many of whom fled fighting further north. Other very serious abuses, including targeted killings have been reported from areas held by forces of the National Congress for the Defence of the people commanded by Laurent Nkunda."
The UN human rights chief urges the Congolese government to take swift action to control its soldiers and protect the civilian population.
She also calls on the international community to help the government put institutional reforms in place so that its security forces can play their appropriate role under the constitution.
This is Donn Bobb reporting for United Nations Radio.
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