Amnesty International says rebels active in North Malaita in Solomon Islands are thwarting efforts to maintain law and order.
The organisation has revealed that kidnapping, rape and torture has gone unchecked in the country despite assistance from the Australian-led assistance mission, RAMSI.
In its 2005 report it says that authorities have failed to punish many responsible for violent crimes against women during the ethnic tension between 1998 and 2003.
London-based Heinz Schurmann-Zeggel, the head of the Australia-South Pacific region at the international secretariat, says victims are reluctant to come forward.
"In North Malaita it is particularly difficult for RAMSI and for the local police, because there are still people with automatic rifles around, with illegal weapons in the bush. It's the Malaita separatist rebel group which has been active in the area, so people there are even less willing to co-operate with the justice system, to go to court and be a witness."
He says there are cases involving allegations of torture where police have got witnesses, but women are refusing to testify.
He believes raising awareness about the seriousness of violence against women is crucial.