Amnesty International says refugees and asylum-seekers are stressed and anxious as they wait for the Manus Island detention centre to be closed today.
There are fears of violence in Papua New Guinea between local authorities and more than 700 men who are refusing to leave the Australian-run immigration centre.
Immigration authorities want to move the men from the detention centre to three other sites on the island, but some fear they will be attacked by locals who do not want them there.
A Pacific Researcher for Amnesty International Kate Shuetze in Papua New Guinea said it felt like the calm before the storm, as refugees said emotional goodbyes.
She said there was an increased presence of security and military officers.