The United Nations is investigating around 150 allegations of sexual abuse by UN civilian staff and soldiers in the Democratic Republic of Congo.
A senior UN official said the accusations include allegations of paedophilia, rape and prostitution.
The official said there was photographic and video evidence for some of the allegations and most of the charges came to light since last spring.
The UN Secretary-General, Kofi Annan, expressed outrage at the abuse.
Mr Annan said the allegations concerned a small number of UN personnel and promised to hold those involved accountable.
He said he had long made it clear that his attitude to sexual exploitation and abuse was one of zero tolerance, without exception.
Nearly 11,000 UN peacekeeping troops are serving in the country, where fighting between ethnic militias has killed 50,000 people since 1999.
