A search is underway on Lake Rotoroa in central Hamilton after a body was discovered on Friday.
A post mortem on the body of a 43-year-old woman revealed her death was not suspicious.
However, the police say there are still a number of unaswered questions.
The Waikato Search and Rescue Squad returned to the lake, which is also known as Hamilton Lake, at first light on Tuesday to conduct another search.
Police say the situation will be reassessed once the search is over.
