A police investigation is under way after a three-month-old baby was brought into Christchurch Hospital with serious injuries on New Year's Eve. 

Detective Inspector Michael Ford said a scene examination was taking place at a home today on Cuffs Rd in Wainoi to help determine what had occured. 

He said police were keen to speak with people who knew how the infant had come to suffer the non-accidental trauma. 

"We are appealing to anyone who may have information as to how the baby sustained the injuries to come forward and speak to us," he said. 

Anyone with information was asked to contact Christchurch Police on 105 and quote file number 211231/7575. They could also provide information anonymously by calling Crime Stoppers on 0800 555 111.