The New Zealand journalist Barbara Dreaver was not detained, as had been reported, but she voluntarily accompanied police to help them with their enquiries, according to the Nauru government.
Ms Dreaver, who was stopped by police while speaking to a refugee, has now had her accreditation to cover the Pacific Forum summit revoked.
No journalist on Nauru has been prevented from talking to any person including refugees, according to local authorities, but they need to go through the proper channels in order to visit or approach the refugee camps, or report from outside the Forum summit.
Ms Dreaver didn't follow procedures, acording to an official statement, which said potentially risks the safety and security of herself and others.
The Nauru government said via Twitter it expects to be portrayed as preventing press freedom, but said this is not the case.
Police and security agencies are genuinely concerned about safety and security risks, said the official statement, should media take it upon themselves to enter the camps where it said emotions are high.
Nauru is a sovereign country which has the right to protect its citizens and residents, said the government statement, and it doesn't apologise for its action.