A plane chartered by the Australian Government with about 20 serious criminals is due to land in New Zealand as early as Thursday.
The Government will this afternoon seek to urgently pass legislation to enable deportees from Australia to be monitored in the same way as if they had served prison time here.
Justice Minister Amy Adams said she understood the majority of the deportees on the plane would come from the detention centre on Christmas Island, and that some had committed serious crimes.
"I understand they have sent information dossiers in respect of each of the people arriving...we have a rough idea of the types of offences...they certainly include sexual violence, serious violence, robbery."
Labour has said it has no choice but to support the urgent law change, but has criticised the Government for being much too slow to react to the issue.
Following a law passed by Australia a year ago, resident visa holders who have served a term of imprisonment for a year or more automatically lose the right to reside in Australia - it used to be two years or more.
Ms Adams defended the Government's response, saying the Australian law had been passed three days before Christmas, and she was first briefed on it in February.
She said it was her understanding that murderers, rapists and child sex offenders were among the criminals who had already been deported to New Zealand this year, and who were under no obligation to co-operate with authorities.
"Murderers, rapists and sex offenders have been coming to New Zealand unsupervised for years and years and years," Ms Adams said. "This is not a new issue. What we are now having is more of them."
Ms Adams has previously said that existing supervision orders could be used to monitor the most serious offenders.
Asked why none had been used, given recent deportees have included those convicted of very serious crimes, she said that was a matter for the chief executive of Corrections, Ray Smith.
"I haven't been through the risk profile of any of the offenders who have arrived, that is his job, his role."
Labour leader Andrew Little this morning said his party had no choice but to support the urgent legislation.
"The reality is, the Government has handled this so badly. A situation they have known nearly a year ago was upon us, they have now introduced legislation to deal with it.
"They have a plane-load of roughly 20 deportees ready to come out of Australia. For the sake of New Zealanders' safety and security, we won't have much choice but to support it."
Mr Little said Labour had put a proposal which would see the Government introduce two bills, one under urgency and one under the usual process, allowing public input through the select committee stage.
The urgent bill would ensure deportees were adequately supervised, but would contain a sunset clause and expire once the other legislation was law.
"They have rejected that proposal, but through the urgent legislation we will continue to press that case, and see if we can get some movement on it."
The plane arriving this week will carry New Zealand citizens who have lodged appeals against their deportation from Australia.
About 40 Kiwis are thought to be in detention on remote Christmas Island where riots and fires just over a week ago caused about $11 million in damage.
Prime Minister John Key last night told reporters in Vietnam that the chartered plane was evidence that, "the message has got through that they actually can go and register their appeals from New Zealand".