1 NEWS Pacific correspondent Barbara Dreaver has been released, after being detained by authorities in Nauru while covering the Pacific Islands Forum.

1 News Pacific Correspondent Barbara Dreaver Source: 1 NEWS

She was being held at a police station after being detained at about 1pm, but The Ministry of Foreign Affairs and Trade has just said she has been released at around 4.50pm.

Barbara Dreaver outside the Nauru police station after being detained for three hours. Source: 1 NEWS

She has been stripped of her media accreditation for the forum.

The Ministry of Foreign Affairs and Trade told 1 NEWS it's understood Dreaver may be accused of breaching the conditions of her visa.

Most countries have only been able to send three journalists and the visa states the journalist can only report on the Pacific Islands forum and related events.

Nauru officials are considering whether to deport Dreaver. If they did so that would be on the next plane out of Nauru, which is tomorrow night.

Head of News and Current Affairs John Gillespie said it was highly concerning a journalist doing their job had been detained.

Her cameraman says he and Dreaver had visited a settlement to speak with a refugee.

Within a minute of going into the cabin of the refugee's mother, security knocked and asked if they had permission to film.

Dreaver said the Prime Minister of Nauru the previous night had said restrictions on interviewing refugees had been relaxed.

The security team said they needed that in writing, so Dreaver and her cameraman said they would get something and return.

The exchange was civil.

Prime Minister Jacinda Ardern has just told 1 NEWS she is pleased Dreaver has been released.

She says it's still not clear to her why she was detained, but it’s understood to be around the visa restrictions.

Ms Ardern says she will raise it with her counterpart when she travels to Nauru tomorrow. She will be seeking assurances that New Zealand journalists in Nauru at the moment will be able to continue to do their job.

She says the New Zealand Government believes in and will defend freedom of the press, and that New Zealand journalists should have the same freedoms when they are working overseas.

AUTHORITARIAN GOVERNMENT

The increasingly authoritarian Government in Nauru has targeted opposition MPs, the judiciary and freedom of speech.

Nauru is home to an Australian detention centre with more than 900 refugees and asylum seekers on the island – about 100 of them children.

Australia's ABC was told not to bother applying for a visa as the Nauru administration felt its coverage was biased.

Other media groups were denied visas, as were some non-government organisations which have been outspoken about the refugees on Nauru.

The Nauru government released a statement this evening, denying she was detained, but saying Dreaver 'voluntarily' accompanied them while they made inquiries.

They accused her of failing to following "procedures" for reporting outside the forum.

Dreaver has faced issues covering Pacific Islands stories in the past. She was banned from Fiji for eight years over a 2008 story that highlighted poverty in a Fijian village.

The 1 NEWS reporter spent time in a Fijian detention centre before being allowed to return home.