An immigration lawyer says tracking down about 40 Tongan nationals whose criminal records were cleared so they could obtain New Zealand visas, will be a challenge.
Yesterday, the Government put an immediate hold on Tongan visa applications that require a police clearance, as Tongan police records had revealed 172 people were unlawfully cleared so that they could travel.
The Government says immigration officials are seeking about 40 people and they have some names but not birth certificates.
An immigration lawyer for Pacific Legal, Richard Small, says some of these people may have been in the country for many years under different names.
"If people have been prepared to be fraudulent with their police certificates, who knows what other certificates there may be. That means that this could be a protracted process, and it will depend on how long ago, I think in parts that these events happened."