It is unacceptable that a teenager was forgotten at an Auckland government office and found by cleaners after hours, Children's Minister Anne Tolley says.
The child, now identified as a 14-year-old girl, was left behind at an Auckland Ministry for Vulnerable Children office. Initially she was reported to be a boy.
She was found in the evening by cleaners, who called the police. Police went to the office and contacted ministry staff.
Mrs Tolley said it was an operational matter and she had asked the ministry to look into the case.
The social worker who told RNZ about the situation said forgetting a child like that was unusual, but children often sat in ministry offices all day while staff struggled to find a place for them to stay.
"It wouldn't be unusual for children or young people to be waiting in the office all day because there's no placement for them or a placement has been arranged but it's not ready."
The Ministry for Vulnerable Children has issued a statement echoing Mrs Tolley's, saying "the situation of a young person being left in one of our offices unsupervised is completely unacceptable".
Deputy chief executive Glynis Sandland said it would not want any child to be left alone like that, or for it not to know where a child was.
There were a number of points on the day in question when that could have been prevented, she said.
There were two family group conferences underway in the office at the time, which led other staff to believe the girl was being cared for, Ms Sandland said.
"While this created confusion it in no way excuses such an unacceptable mistake."
The situation unfolded six weeks ago when the girl was taken to the office at 1pm by police, who advised a ministry supervisor they were taking her there.
She was placed in a quiet room and went to sleep, Ms Sandland said.
"A family member later arrived to collect her, but left before staff went and got the girl."
Ms Sandland did not explain why the family member had left without taking the teenager.
The staff left the office for the day at just before 7.30pm, leaving the the girl on her own before she was discovered by cleaners just before 8pm.
The ministry said the girl was now living with family.
It has launched an employment investigation into the matter.