Residents in Totara Park, Wellington, are being asked to check their properties for missing man Brett Carpenter.
Police have serious concerns for the 60-year-old's welfare, he has Alzheimer's and was last seen on Hartford Crescent Street, Totara Park about 12pm.
A Search and Rescue operation is under way in the wider Upper Hutt area. Detective David Nichols said residents would see an increased presence of Police and Land Search and Rescue personnel.
"At this stage, the best thing people in the area can do is check their properties and structures for Brett and call Police on 111 immediately if they find him."
Brett is tall, skinny and Caucasian, with grey hair and an unshaven face.
He was last seen wearing a black sweatshirt, and black trackpants with white stripes on the leg.