A crackdown on immigration scams following the 2001 terrorist attacks has led to a steep rise in the number of charges being laid against potential fraudsters.
The doubling of staff numbers in the Immigration Service's fraud unit is being credited with an almost four-fold increase in the number ofcharges involving people trying to trick officials.
In the year ended June charges were laid in 182 cases compared with 48 cases the previous year, according to the Department of Labour's annual report.
In most cases, charges have led to or are expected to lead to convictions.
National fraud manager Terry Pawson told the Herald the cases involved both individuals and immigration agents.
Most cases involved people presenting false documents or information in support of a visa or permit application.
The charges do not involve passport cases.
In last year's Budget, the Government increased funding to double the number of investigators in the Immigration Service's specialist fraud unit, from four to eight.
That decision followed the September 11 attacks in the United States, and increasing pressure on Governments to monitor immigration.
Mr Pawson said it was not possible to say how much money immigration fraudsters could make, but it was significant.
He said his unit had uncovered one agent in New Zealand who had charged a woman $150,000 for a resident's permit. That was not necessarily illegal, but the woman could have obtained a permit for the price of administration fees if she had simply asked the Immigration Service directly.
According to the annual report, fewer people have been turning up at the border without identification - 143 in the 2003-2004 financial year compared with 260 the previous year - and more people have been refused entry into New Zealand at borders - 869 compared with 570 a year earlier.
