The search for a 5-year-old boy who was swept offshore just before midday has been called off and will resume at first light tomorrow.
The Tauranga boy was playing with two cousins on the water's edge at Mt Maunganui when a huge wave engulfed them.
Four children and two women, also the boy's relatives, were in the extended family group visiting the beach.
The group had been walking around Shelly Beach, near the base of Mt Maunganui, when they stopped for the children to play.
After the wave overwhelmed them, the two sisters aged 12 and 14 climbed on a rock.
The two women rescued the girls, sustaining cuts and bruises in the process.
But the young boy disappeared from everyone's sight, into the sea.
An off-duty police officer in the area saw one of the women making her way out of the water and calling for help just after 11.15am. Sea conditions were treacherous, with three to four metre swells.
A search and rescue operation began, involving Rotorua's BayTrust and Trustpower TECT rescue helicopters, the local surf lifesaving club, Coast Guard, land search and rescue, and police officers.
The boy's distraught mother arrived soon after at Mount Maunganui Surf Lifesaving Club. Two other women, understood to be family members, comforted her. She said her son did not know how to swim.
The atmosphere was tense as searchers found no sign of the boy.
Barely half an hour before the 5-year-old boy went missing, teenage surfer Zedek Macklow found himself in trouble.
Zedek, 13, said there was an unusual rip "all the way across the main beach".
He had been surfing at Mount Maunganui for three years and said conditions were highly unusual today.
Zedek said he was caught in a rip and found himself drifting past Moturiki Island, also known as the blowhole.
"I got taken out, past the blowhole, and called for help to the people on the rocks and they called the lifeguards."
Zedek was saddened to hear of the missing boy, as was his mother Emily.
"It's so terrible. My heart so much goes out to her," Mrs Macklow said.
She was grateful to local lifesavers for rescuing Zedek, and said the sea was deceptively treacherous.
"I think the conditions in the water were worse than [they seemed] being on shore looking at."
Nearby, Coffee Club store manager Tony Lee said the waters where the boy disappeared were abnormally wild, despite the sunny weather. "Those waves out there off the beach are really massive, way higher than usual."
Mr Lee said Mt Maunganui was busy, with many families visiting to enjoy the sunny weather.
Local charter boat operator and fisherman Russ Hawkins said big waves were travelling at speeds of about 30 knots (56km/h) and caused treacherous, unpredictable conditions.
Mr Hawkins said a "depression" or low pressure zone off the east coast triggered today's unusually high, treacherous swells.
"It comes in sets ... every three or four minutes you get an extra big set. Then it settles ... and picks up again."
The search expanded south and west to take in waters of the Tauranga harbour entrance and seas surrounding Matakana Island.
Western Bay of Plenty police inspector Karl Wright-St Clair said it was a "freakish accident" and the two adults supervising the children were not at fault.
"We've told the family we are doing everything we can," Mr Wright-St Clair said.
"The family are devastated. They are a local family with a lot of support from family members and they are being supported by victim support and police."
St John paramedics treated the girls, who were then taken to hospital and discharged.
At 7.30pm the search was wrapping up and the 5 year-old had still not been found. The search will resume again at first light.
Police search for the missing boy. Photo / Alan Gibson
- Additional reporting Bay of Plenty Times