West Papua advocates are concerned Indonesia will launch a military assault in Nduga province, putting thousands of innocent lives at risk, now that New Zealand pilot Phillip Mehrtens has been released.
But the Indonesian government say it is a "baseless accusation".
Mehrtens was held captive for almost 600 days by the West Papua National Liberation Army (TPNPB) in Nduga province.
The United Liberation Movement for West Papua (ULMWP) vice-president Octovianus Mote is asking the New Zealand government to keep watch on Indonesia in case they launch an assault.
He said with Mehrtens no longer being held captive, TPNPB and civilians living in Nduga province were vulnerable.
"The New Zealand government, they really have to pay attention, not only because we took care of New Zealanders [Phillip Mehrtens], we treated him as our family, but New Zealand is our family, anyway we are Pacific Islanders."
He said Indonesia had been humiliated because they tried to portray TPNPB as a criminal organisation and Mehrtens was treated well throughout his time as a hostage.
"The way we released him freely, not through the police and military operation, that's another humiliation," Mote said.
On the day that Mehrtens was released there was no violence, but Indonesian human rights lawyer Veronica Koman said it was wrong to think of the release as peaceful.
In March last year, Indonesian soldiers allegedly attempted to rescue Mehrtens by force, resulting in causalities on both sides.
"West Papuans have died during this saga and thousands have been displaced," Koman said.
"There were causalities and let's not forget them and let's not only focus on this one white man."
In 1996, the Free Papua Movement took 26 hostages from the World Wildlife Fund. Two kidnapped Indonesians were killed with the remaining hostages freed within five months.
Koman said Indonesia's military launched a big retaliation attack once they were freed and she is concerned they will do the same.
"This is based on the pattern where there will be retaliatory attacks and just like this morning there have been attacks by armed clashes in other parts of West Papua.
"I think that's definitely happening given the intensity of the armed conflict."
'Fear of a potential reprisal'
Pacific geopolitical expert and Massey University lecturer, Anna Powles said Mehrtens was long overdue to be released but it's a "bitter-sweet victory".
"There are also strong concerns that have been voiced by Papuan activist leaders of fear of a potential reprisal by the Indonesian military now that the international focus has lifted from Papua."
An Indonesian Embassy spokesperson in Wellington said the Indonesian government is "of the view that this is a baseless accusation".
"The Indonesian military holds a high regard to its integrity to ensure the security and welfare of the people in the region, especially those who live under the threat of continuous attacks and terrors by the armed criminal groups," the spokesperson said.
"The threat from an insurgency does not provide a legal justification for the broad-brush and abuse of military force. Indonesian armed forces are receiving human rights and the law of war seminar and training as part of a wide program."
They said the Indonesian government was committed to "its long-standing policy of respecting and promoting Human Rights" and its strict policy of zero impunity for misconduct by security forces.
'Constructive engagement with Indonesia is critical'
New Zealand's prime minister Christopher Luxon was asked Wednesday if he had thought about or taken advice on the concerns of Indonesia military attack in West Papua.
"That's the first I've heard of those comments, I appreciate it's a challenging situation there and there's an internal conversation there, but we respect Indonesian sovereignty."
A spokesperson for the New Zealand Ministry of Foreign Affairs and Trade said New Zealand continues to register its concerns with Indonesian authorities about human rights concerns in Papua.
"Maintaining open and constructive engagement with Indonesia is critical to improving the situation in Papua, and was key for the safe release of Mr Mehrtens," they said.
"The New Zealand government also acknowledges the patient approach exercised by the Indonesian Military and Police which prioritised the peaceful negotiations needed to ensure Mr Mehrtens' safety."