Internal Affairs Minister Rick Barker says the possibility of immigration fraud in granting residency and citizenship to Auckland man Yang Liu is being investigated.
Mr Barker was responding last night to questions about the circumstances in which Mr Liu, also known as Bill Liu, was granted residency and citizenship.
In a Newstalk ZB interview last night, Ian Wishart, of Investigate magazine, said he had received leaked Department of Internal Affairs documents raising concerns about Mr Liu's true identity.
The minister said Mr Liu was granted permanent residency in January 2002 by an immigration officer.
His application for citizenship was made in May 2005, but was not approved until August this year.
Retiring Labour MP Dover Samuels said he supported the citizenship application of his "personal friend", Mr Liu.
Mr Samuels said Mr Liu's application was approved by Associate Minister of Immigration Shane Jones.
Mr Barker said this was done by Mr Jones under delegated authority.
"All citizenship decisions are made by the Minister of Internal Affairs, except where there may be an actual or perceived conflict of interest," said Mr Barker.
In that circumstance, a decision was made by another minister.
Mr Barker said an investigation was being made into "the possibility of immigration fraud in this case".
He did not want to jeopardise this process, and there would be no further comment from ministers.
Mr Samuels said Mr Liu had been in New Zealand for seven years and there had been procrastination about giving him citizenship.
"He had a falling-out with the Chinese Government," he said.
"He's pro-democracy, some sort of supporter of Falun Gong, and he protested against this Chinese regime in New York. They're after him.
"His wife is a New Zealand citizen, his children are New Zealanders, he's never broken the law here, and I wrote a letter of support to the minister considering his application for citizenship."
Mr Samuels said his understanding was that the granting of citizenship had "got up the nose" of Internal Affairs officials, and they had leaked information to Ian Wishart.
Mr Samuels said Mr Liu was fostered out as a child, and this had led to confusion over his identity, but he had explained this.