The Australian company Canstruct will not comment on the deportation of four of its workers at the Australian-run asylum seeker camps on Nauru.
The Nauru Government is also refusing to say why the workers were sent home.
Canstruct said it had no comment to make on the removals, which RNZ Pacific understands to have been ordered by the Nauru government.
Australia's Department of Home Affairs said visa matters were up to the Nauru government, though it is understood the workers' visas have not been rescinded.
The workers themselves are bound by confidentiality clauses in their contracts.
RNZ Pacific understands the Canstruct workers had raised concerns about the behaviour of a refugee employed at the agency which might have prompted their removal.
In about six weeks time a Nauru run company is set to assume the management of the refugee facilities, with the Canstruct contract coming to an end.