Police have charged a 22-year-old mother with two counts of abandoning a child under six, after a toddler and baby were found alone in a Hamilton house.
Officers were called to the house in the suburb of Dinsdale at 3.30am on Sunday, where police say they found a two-a-half-year-old boy crying outside the front door.
Senior Sergeant Kevin Anderson says an 11-month-old boy was found in a portable cot, with superficial facial injuries.
In the cot, he says, were two ready-to-drink cans, some chips, a bottle of milk formula and a straw and a sealed condom packet.
Senior Sergeant Anderson says officers then searched the house looking for a parent or caregiver, but instead found a bed that had been padded with pillows, apparently to make it look like someone was there.
He says detectives found the mother back at the house just after 9am, more than five hours later.
The children are being temporarily cared for by Child, Youth and Family.
Service has seen few cases like it
A family support service says this is one the most extreme cases of neglect it's aware of.
The chief executive of strategic operations for Jigsaw Family Services, Liz Kinley, says her agency comes across cases nationwide of children being left alone.
She says that very frequently, although it's inexcusable, it's in situations where there is an emergency or people feel they have nowhere else to turn.
It's very seldom, Ms Kinley says, that the agency deals with a situation where the mother has left her children for so long in the middle of the night.