The number of people deported from New Zealand has hit a four-year high.

Figures released from Immigration New Zealand (INZ) show there were 747 deportations in 2016-17, up 205 from the previous year.

It was also the highest number since 2012-13, when 791 people were deported.

Last week Colin Bouwer, the Dunedin psychiatrist who killed his wife with poison, was granted parole on the condition the 67-year-old be released into police's custody for "immediate deportation from New Zealand". That was expected to occur on October 11, allowing time for travel arrangements to his home country of South Africa to be made.

Removal and deportation cost the department $1.7 million in 2016-17 – the highest in five years.

Figures on how much deportees reinbursed the Government for their removal were unavailable, but deportees were made aware of the costs beforehand.

An INZ spokesman said anyone staying in New Zealand longer than their visa allowed was unlawfully in the country and could be liable for deportation.Those people might be allowed more time to depart voluntarily or they had to get a new visa. INZ could serve a deportation order once their appeal rights expired.

Those engaged in criminality were the highest priority for deportation. The vast majority of those unlawfully in New Zealand were not criminals and the department assisted them towards "voluntary departure", the spokesman said.

The number of voluntary departures for 2016-17 was 1437, up 83 from the previous year, and the highest number since 2012-13. 

(Source: Stuff, Catholic News NZ)