Papua New Guinea police has confirmed that a PNG woman held hostage by armed criminals in the Southern Highlands was released to them this week.
Deputy police commissioner of police operations Dr Philip Mitna said the woman is now with police whilst negotiations are ongoing to secure the release of the other four.
The ABC has reported an Australian professor and his colleagues were taken hostage in a remote area of Papua New Guinea a week ago.
Police Commissioner David Manning reiterated that police are authorised to use full force of the law to secure the people being held, and to immobilise and apprehend the criminals.
However, he said the police are offering the abductors a way out.
Manning said the kidnappers can release their captives and they will be treated fairly through the criminal justice system, but failure to comply and resisting arrest could cost them criminals their lives.
"Further information will be released by the RPNGC as and when further details can be made available by Deputy Commissioner Mitna as the Chief of Police Operations," Manning said.
The National newspaper reports Prime Minister James Marape as saying the full names and pictures of the 13 people involved in the kidnapping are with police.
Marape has urged the group to release all the remaining hostages.