The group said Canadian-owned Barrick Gold had employed security guards at Porgera who had committed killings, assault, and rape.
Its executive officer, McDiyan Robert Yapari, said an ombudsman would finally provide some justice for victims as well as holding mining companies to account.
"Now we don't have any choice but only our prayers - our only hope now lies with the Candian Prime Minister, if he sets up this Canadian extractive human rights ombudsman - that would be a great relief for us," said McDiyan Robert Yapari.
Mr Yapari said the situation at Porgera Mine was getting worse and an ombudsman was the community's last hope. RNZI