Corrections is defending its decision to place two high-risk sex offenders in a Hamilton boarding house where young kids were living, saying staff "did not see any children present".

But the department is under fire amid allegations it failed to properly vet the accommodation.

The Herald revealed yesterday that two men with convictions for sexual offending against children have been living in the Hamilton boarding house with boys as young as 4-years-old.

They were arrested and remain in custody after it was discovered they had breached the conditions of their extended supervision orders, which stated they were not to be near children under the age of 16.

One of the men has also committed violent crime, including kidnapping a man at knifepoint and threatening to kill.

Asked yesterday about the decision to place the high-risk abusers in shared accommodation near children, Corrections central regional commissioner Terry Buffery said Community Corrections staff "did not see any children present or indications that children were present, neither were they told that children would be present".

"Both offenders were supervised by the probation officer and subject to GPS monitoring and as soon as they were known to be in breach of their conditions, action was taken," Buffery said.

"Public safety is Corrections' primary priority. No offender would be placed at an address if it was considered that their risk could not be safely managed."

Buffery said Community Corrections worked with organisations such as Work and Income, New Zealand Prisoners Aid and Rehabilitation Society and the Salvation Army when considering housing options for offenders.

Corrections Minister Judith Collins initially directed all questions to Corrections staff.

Labour's corrections spokesman, Kelvin Davis, said Collins was failing to front up over the issue.

"Personally, if I was the minister I would've said, 'That's just not good enough and I'll look into it,' instead of just doing the old Pontius Pilate and wiping her hands of it and putting it on to everyone else."

Davis was also critical of the measures undertaken by Corrections ahead of placing the two sex offenders.

"It's pretty pathetic really ...

"You've got to ask how rigorous their procedures are, you can't just make assumptions.

"You've got to actually do a bit of digging and looking, and obviously they got it wrong big time."

A spokeswoman for Collins later issued a statement saying that legally the minister could not become involved in decisions about individual offenders.

"The decision about where to place offenders is made by Community Corrections."

Asked if Collins was satisfied with the measures undertaken by Corrections to check children were not living in the boarding house, the spokeswoman said a significant amount of preparation went into approving a suitable residential address for an offender being released from prison.

"I understand Corrections has already advised you that no children were living at the boarding house when it approved the address."