Three out of four women in parts of Liberia have been raped, a survey has found. Girl children are especially vulnerable - some victims are as young as three.

The medical aid agency Merlin sees between one and four cases of child rape at the clinics it supports in Liberia every month. And Claire Parker, Merlin's reproductive health co-ordinator, says that is only a small proportion of the victims.

"Close to 50 per cent of reported rapes here are in under-12s," she said. "If a person is seeking a position of power here, there is a traditional belief which says that if you spill the blood of a child, or take the virginity of a child, that will give you increased power," she says.

In January, an 11-year-old girl, Janjay, died from injuries sustained during a particularly violent rape. "It left her incontinent ... she wasn't able to walk properly, she was out of school. Her injuries contributed to her death," Ms Parker says.

President Ellen Johnson-Sirleaf, Africa's first elected woman president, has promised to come down hard on rapists and end the sexual violence.

She has appointed a Minister for Gender in Liberia, and last December, passed a law making gang rape illegal for the first time.

But the 14-year conflict has left Liberia's judicial system in tatters. "The vast majority of rape cases don't even make it to a conviction, let alone to the imprisonment of the perpetrator," Ms Parker says. "People are reluctant to report rape cases because of the shame that goes along with it ... and if they do report it, they sometimes can't afford to take it forward to court.

"The President is certainly doing a great deal to inform normal women here that they do have rights," Ms Parker says. "And really, in Liberia, you have to start at grassroots level."