A dozen senior officers in the Congolese army have been arrested for responsibility for mass rapes committed by several army units in eastern Congo in November 2012, Congolese Justice Minister Wivine Mumba told The Associated Press Saturday.

The arrests come more than two weeks after the United Nations pressed the Congolese government to take action in the case. The U.N. said that if the Congolese government refused to prosecute the suspects, the U.N. peacekeeping mission in Congo, known as Monusco, would suspend its collaboration with the army units suspected of committing the rapes.

"The human rights division of the Monusco carried out an investigation and presented its results to the government and the army. We have a policy of conditionality regarding our collaboration with the Congolese army. If no action had been taken we would have suspended our collaboration with the said units of the Congolese army," said Madnoje Mounoubai, the Monusco spokesman in Kinshasa.

The mass rapes occurred in November, 2012, after the Congolese army was defeated by the M23 rebels who seized the provincial capital of Goma, in eastern Congo. The national army retreated in disorder.

Commanders lost control of their troops, or were unwilling to impose discipline over their men who regrouped some 50 kilometers (30 miles) south of Goma, in Minova. A small, dusty town on the shore of lake Kivu, Minova is home to several thousand people. For days, the Congolese army raped, killed and looted in anger and disarray after their defeat, before discipline could be re-established by army commanders.

"It was difficult to carry out an investigation at a time of war and to know what units committed the crimes," said Justice Minister Mumba.

She said she sent a special undercover team to investigate the allegations. "It was difficult to find proof. We know that many women were raped, but who exactly did that was hard to find out," she said.

An estimated 126 women were raped by army soldiers, according to a report by Human Rights Watch. But Mumba said the government investigation found that the numbers were likely higher.

"There are women who, because of our traditions that push aside raped women, did not dare to come forward to tell their story," said Mumba.

Suspects and victims will be interviewed by Congolese military prosecutors before the trial. Congo has a track record of letting crimes of sexual violence go unpunished, in particular when committed by the military. The culture of impunity pervading all levels of Congolese society has created an environment prone to sexual violence because perpetrators do not fear being prosecuted.

Mass rape is a crime against humanity and a war crime under international law.