Denis Mukwege, a Congolese doctor who runs a hospital for abused women and children in eastern Congo, says the youngest rape victim he has treated was just three years old.
After being honoured with a UN human rights prize in New York on Wednesday, Dr Mukwege said the world should do more to end the conflict in the Democratic Republic of Congo that has killed and displaced millions of people over a decade.
"The crisis that is happening in Congo is treated with unimaginable hypocrisy," Dr Mukwege said in an interview after the awards ceremony.
"Everyone knows. More than five million dead, and everybody knows. Reports say 50,000 to 60,000 women are raped every year."
Dr Mukwege said the 17,000 UN peacekeepers were little more than observers and needed a much stronger mandate to act.
"I always wonder, where is the political will to change the situation? I think the political will does not exist."
Rebels and government officials are in Nairobi this week for the first face-to-face talks to defuse renewed tension that has threatened to trigger another regional war.
The talks were aimed at ending fighting in Congo's North Kivu province between the military and Tutsi rebels loyal to General Laurent Nkunda. The fighting has displaced a quarter of a million people since August.
Dr Mukwege runs the Panzi Hospital for rape victims in Bukavu, which treats 10 to 12 women and children a day. Before the new clashes, patients were coming in who had been raped a year or more ago, but now he is seeing a sharp rise in new cases.
"What happens to the children is even more brutal," Dr Mukwege said. "The youngest child I have treated is a child of three with the rectum and the vagina completely torn apart."
Although Congo held successful elections in 2006 aimed at ending a decade of war and chaos, violence has simmered in much of the east, where chaotic rebel and army units roam, often looting and targeting civilians.
A UN report last month said government and rebel groups have committed serious human right abuses, including mass killings, rape and torture.
Dr Mukwege said rape was used both as a weapon of war by individual soldiers and a "strategy of war" by groups determined to destroy communities and drive people from their land. "It is done with an element of spectacle, in public, in front of everyone - with humiliation," Dr Mukwege said.
He said the international community should address the root cause of the conflict, a struggle for natural resources.
"If the international community put pressure on the actors of the war in the Great Lakes region, it could stop immediately," said Dr Mukwege. "It's not a civil war, it's not an ideological war, it's more an economic war."
The UN has a 17,000-strong peacekeeping mission in Congo, known as MONUC, and has asked for an EU "bridging force" to reinforce it until 3,000 more UN troops and police arrive next year. EU ministers are split on how to respond.