More than 1,000 civilians have been killed and nearly 900,000 displaced in eastern Congo by Rwandan Hutu militiamen and Congolese forces since January, humanitarian groups said Tuesday.

The report released by a coalition of 84 organizations said that many of the killings were carried out by Rwandan Hutu militiamen. Congolese government soldiers also have targeted civilians, the report said.

A Congolese military operation has been aimed at forcing out the Rwandan Hutu militiamen, many of whom sought refuge in neighboring Congo after participating in Rwanda's 1994 genocide that killed more than 500,000 people.

But the groups said Tuesday that the military operation, which is backed by a United Nations peacekeeping force, is not doing enough to protect civilians in the region.

"The human rights and humanitarian consequences of the current military operation are simply disastrous," said Marcel Stoessel of Oxfam.

The U.N. peacekeeping mission in Congo, known as MONUC, has backed the Congolese army in eastern Congo since March following a joint Congolese and Rwandan operation against the Rwandan Hutu militiamen.

A U.N. spokesman declined to immediately comment Tuesday on the report. However, U.N. officials have said that they simply do not have enough boots on the ground to perform effectively in Congo, a country that is bigger than Western Europe but with only 300 miles of paved roads.

The 3,000 additional U.N. peacekeepers authorized by the U.N. Security Council in November 2008 are only just arriving in the region, the report said.

"The U.N. needs to make it clear that if the Congolese government wants its continued military support, the army should remove abusive soldiers from command positions and its soldiers should stop attacking civilians," said Anneke Van Woudenberg, senior researcher at Human Rights Watch.

The report said that many of the killings have been carried out by the Rwandan Hutu militiamen "targeting civilians to punish them for their government's decision to launch military operations against the group."

Congolese government soldiers also have targeted civilians through killings and widespread rape, looting, forced labor, and arbitrary arrests, the report said.

"Nearly 900,000 people have been forced to flee their homes and live in desperate conditions with host families, in forest areas, or in squalid displacement camps with limited access to food and medicine," it said.

The report also said that 7,000 women and girls have been raped and more than 6,000 homes have been burned down in the eastern provinces of North and South Kivu.

The humanitarian groups also called for those wanted for genocide and other serious crimes to be brought to court, including militiamen living in Europe. The groups also said that those responsible for serious human rights abuses, including sexual violence, should be prosecuted regardless of rank.

The 84 groups in the coalition behind Tuesday's report include ActionAid, Human Rights Watch, International Crisis Group and Oxfam.