A smuggler for one of the biggest methamphetamine syndicates in New Zealand was able to obtain citizenship before officials learned of his crimes.
Xing "Alex" Su was a police target in Operation Colossus as he travelled back and forth between China and New Zealand to organise the supply of pseudoephedrine, the main ingredient in P, for a drug ring in Auckland.
He was later convicted of importing the Class C drug and manufacturing methamphetamine and sentenced to more than four years in prison in 2009.
However, the Herald has learned Su obtained New Zealand citizenship as his drug crimes occurred while the application was processed.
He was deprived of citizenship in June 2010, one of 22 cases where citizenship has been revoked in the past 10 years. Su was deported after he was paroled later that year.
The case summaries were released under the Official Information Act after the most recent citizenship deprivation of Salam Mansoor Abdelabbas Al-Bawi in February.
The department refused to release the names of the 22 people for privacy reasons, including Su and others who have criminal convictions.
Another was a drug smuggler called Maciek Bogdan Korczowski.
The Polish national had been granted citizenship despite his arrest in New Zealand on charges of importing amphetamine from his home country.
Further investigation found he was wanted on forgery charges in Poland.
He was later found guilty of the drug offences in 2000, but skipped bail on the last day of his trial and went on the run for a year until being caught in the South Island.
He was deported in June 2005 after serving less than half of his eight-year sentence.
The most recent revoked citizenship is that of Al-Bawi, who failed in a High Court appeal in February to overturn the decision.
Al-Bawi was sentenced to six months' home detention in 2008 after he admitted lying in order to gain refugee status, residency, citizenship, and a passport under the name John Jacob Abrahim Joseph.
22 citizenships have been revoked in the past 10 years. No names have been released.
Herald inquiries have uncovered four identities.
* June 2004: Maciek Bogdan Korczowski
* September 2009: Ping "Pamela" Hao.
* June 2010: Xing "Alex" Su.
* March 2012: Salam Mansoor Abdelabbas Al-Bawi.