The teenager missing at sea after getting caught in a rip at Whatipu Beach has been named as Leka Pasiaka.
And as tributes and messages of hope flow - the Avondale teenager is being described as "brave as hell" for saving the life of his sister before he was swept out to sea.
The 16-year-old got stuck in a rip at the beach, 45 minutes west of Auckland city, at about 1pm on Saturday.
Leka was at the beach with family and his sister raced into the water to help him.
A witness said the sister swam out to Leka and they both got dragged out together.
Leka then let her go and pushed her away.
She managed to get back to shore but he was swept under water.
His family have remained at the beach, gathering in numbers as the search - conducted by police, Coastguard and volunteers - continues for the youngster.
His sister was rushed to hospital on Saturday but has since been discharged.
It is understood she went straight back to the beach to wait for Leka to be found.
Tributes have been posted online for Leka by family and friends who are struggling to comprehend what has happened.
They are using the social media hashtag #prayforleka and asking the community to keep him in their thoughts.
Posts have appeared on Facebook, Twitter and Instagram with photographs of Leka and messages of hope and support for his family.
On Facebook, those who knew the missing teen have been pleading for him to come back home.
"That was brave as hell, but please find a way... to shore," said one friend.
"Come out of the ocean, enough with the swimming the water it's cold come out and get [warm]. You have been missing for almost a day now," another posted.
"Please keep Leka Pasiaka in your prayers as he's currently lost at sea. I hope he finds his way back to shore," another said.
"Leka Pasiaka Please come back to us we love [you] always," another posted.
Emergency services frantically tried to find and rescue Leka on Saturday.
They were called at 1.30pm and the Huia fire brigade was first to arrive, followed by lifeguards from Karekare - the nearest manned beach - with jet skis and inflatable rescue boats.
Whatipu, a black sand beach on the north side of the Manukau Heads known for its strong currents, does not have surf lifesavers.
Two Coastguard vessels, the Westpac Rescue Helicopter, and several local boats joined the search, largely focusing on the area between Ninepin Rock and Paratutae Island where the boy was swimming.
Another woman at the scene had to be treated by paramedics after she collapsed.
The rest of his family waited, distraught, at the water's edge.
One man, thought to be his brother, refused to leave even after most of the rescuers had gone.
A family member told the Herald they were having a barbecue at the campground nearby when they heard the Leka was missing.
"We came down straight away when we heard he was swept out," he said.
Surf lifesaving patrols were also involved in two rescues at Sunset Beach, Port Waikato on Saturday.
On Sunday they completed 10 rescues at Muriwai, one at Piha and one at Whangarei Heads.
-additional reporting Luke Kirkness