Four workers for an Australian company managing refugee facilities on Nauru have been flown back to Australia without explanation.
The removals were ordered by the Nauru Government, which had the four flown off the island late last month.
Another worker was removed in the same fashion in December last year.
RNZ Pacific understands the Canstruct employees had raised concerns about the welfare of some of the inmates in the camps.
This comes as a Nauru government company prepares to take over the management of the camps in two months' time.
The Nauru Refugee Processing Centre Corporation is reportedly set to run the facilities, paid by the Australia Government, from October.
Legislation establishing the government agency was passed last year.
This will bring to an end five years of management of the camps by Australian companies..
Some workers, who are not able to reveal their identities, had raised doubts about Nauru's ability to provide the services required.