Two babies have died suddenly in Hastings and a third is fighting for his life with serious head injuries and multiple fractures.
Detective Senior Sergeant Dave Greig of the Eastern Child Protection Team said last night both deaths occurred in circumstances that required investigation.
"We can't elaborate further on the circumstances of either death. We are awaiting the final post-mortem results and are not in a position to comment further at this point."
He was unable to comment on whether the deaths were considered non-accidental.
The deaths included a 2-month-old girl who died in Flaxmere on October 21. Slightly more than two weeks later, on November 5, an 8-month-old girl died in Hastings.
Flaxmere resident and Hastings district councillor Henare O'Keefe said he knew of the Flaxmere fatality and had attempted to visit the family.
"I was aware of the death but not the circumstances. I went round there but there was no one home," Mr O'Keefe said.
He said he did not want to pre-judge what had happened and did not personally know the family.
"It's far too young, at two months old they have barely taken a gulp of air."
Police are also investigating how a 5-week-old baby boy from Waipukurau received multiple injuries, including a serious head injury and multiple fractures.
He was admitted to Hawke's Bay Hospital on November 1 but was transferred later that day to Starship Hospital. The boy remains in a critical condition.
Police said a full scene examination had taken place at the Porangahau Rd house where the boy was living and interviews had been conducted with his parents and extended family.
"At this stage we are unable to provide any more detail about the incident, as it is still under investigation," Mr Greig said.
Hawke's Bay based Children's Commissioner Russell Wills said he was not able to comment while the cases were being investigated.