Murdered 5-year-old Malachi Subecz was known to Oranga Tamariki, Children's Minister confirms

Both Oranga Tamariki and Children's Minister Kelvin Davis have promised to look into what went wrong in the agency's dealings with Malachi Subecz.

Warning: This story details graphic child abuse and may be distressing for some readers.

The head of the agency tasked with the care of New Zealand's most vulnerable children says he will be investigating how the system failed 5-year-old Malachi Subecz, who was killed by his caregiver.

Oranga Tamariki acting chief executive Chappie Te Kani called Malachi's death "devastating" and said the agency had been in contact with the young boy's whānau.

It comes after Children's Minister Kelvin Davis told media at Parliament on Tuesday that Malachi had some involvement with Oranga Tamariki.

But the extent to which the ministry had involvement with Malachi and his care arrangements is still unclear.

Malachi was living in Te Puna, on the outskirts of Tauranga, when he suffered months of violent abuse at the hands of Michaela Barriball - the woman entrusted to care for him.

The details of the harrowing murder were first publicly reported this week, with Barriball having pleaded guilty to the killing late last month.

The summary of facts showed Malachi was thrown against walls, held underwater in a bath and made to stand for prolonged periods of time.

He was also severely malnourished at the time of his death, weighing just 16 kilograms.

Blunt-force injuries sustained at the hands of Barriball on November 1 last year led to Malachi suffering a brain haemorrhage. He died at Starship Children's Hospital on November 12.

In a statement this week, Te Kani said he was in the process of establishing exactly what involvement the ministry had with Malachi.

"We need to get to the bottom of why this happened, whether there was more we could have done, and what we can do to ensure such an awful tragedy never happens again.

"This is an absolute priority for me and I will have more to say in the coming days."

The agency was set to meet with Malachi's whānau, Te Kani said.

Davis, who is responsible for Oranga Tamariki, also said his thoughts were with the boy.

Children's Minister Kelvin Davis says he has received a briefing on Oranga Tamariki's involvement with murdered child Malachi Subecz. Photo / NZME

"This is a tragic situation and my heart goes out to the young fella, but I really want to get to the bottom of it," Davis told media on Tuesday.

Speaking to Open Justice today, the minister confirmed he had since been briefed by Oranga Tamariki on the case. "I have discussed this case with Oranga Tamariki officials, and am continuing to receive information on the case.

"Oranga Tamariki are working through their review processes for this case and will provide updates on this when appropriate.

"I have made my expectations clear, and expect Oranga Tamariki to act appropriately in their work."

According to the court documents, Malachi was in Barriball's care as a result of an arrangement with his legal guardian.

Barriball is scheduled for sentencing on June 30.