The Police National Dive Squad is on its way to Lake Rotoiti to help look for a person who was seen to "go under" on Lake Rotoiti yesterday.
Police confirmed this morning they were still undertaking a search and rescue rather than a recovery operation but said they were unable to release specifics to the media.
Squad second in charge, Constable John Fredericksen, told the Rotorua Daily Post he was planning to speak to the family this morning to "ascertain whether they've advised all the people they need to".
He said police were still unable to release if the person was a man, woman or child or if the person was swimming, fishing or on a boat.
He said he hoped to release more details later today.
A police media spokeswoman said this morning a member of the public had seen someone "go under" about 3.45pm on Lake Rotoiti yesterday, sparking a coastline and water search using members of the Rotorua Rotorua Police Search and Rescue Squad and Coastguard.
She said the dive squad was being brought in today to help.
The Rotorua Daily Post went to Lake Rotoiti yesterday and saw the Coastguard and other boats in the area between Curtis Rd and Lake Okataina Rd.