Surfers pulled up to 20 swimmers from the water on the typically calm beach at Hahei on the Coromandel Peninsula this afternoon during a rough day in the ocean.
Emergency services responded to an alert of up to 20 people being swept out to sea at the unpatrolled Hahei beach about 2.15pm.
A Fire Service spokesman said only two who were rescued needed treatment on the beach after swallowing water while caught in the rip.
Surf Life Saving New Zealand club development officer Matt Williams said it was a dangerous day for swimmers to be wading into the water on unpatrolled beaches.
"Hahei isn't normally a dangerous beach [but] it wasn't the day to swim,'' Mr Williams said.
"If you're going to go to a beach, make sure you swim between the flags. We push our Find a Beach website ... it tells you where the nearest patrolled beach is.''
It comes a day after a man drowned at Himatangi Beach.
Jarrett Simeon, 27, of Feilding, is believed to have been swimming outside the flags when he drowned at Himatangi Beach yesterday.
Police found his body about 100 meters from the Himatangi Surf Life Saving Club just before 6am today after he drifted away from a group of friends while swimming about 2.30 yesterday afternoon.
Himatangi Beach Holiday Park owner Dennis Penney said the beach was patrolled by the surf club and had flags, but he understood Mr Simeon had not been swimming between them.
It was about the third drowning he knew of in the 10 years he had lived in the beachside community.
He described the beach as not very deep.
"It runs very shallow, but there can be rips out there at times,'' he said.
"It's not like [Auckland's] Piha or somewhere, but there is rips just about anywhere you go.''
The beach could be driven on, with many people making day trips to the beach.
"You can drive onto the beach ... if you go down there, as far as the eye can see north and south you'll see cars. It's just absolutely loaded.''
Mr Simeon had been swimming with his partner and friends.
A man and his 8-year-old son needed to be winched to safety after rising tides trapped the pair on rocks at Whakatane Heads this afternoon.
The TrustPower TECT rescue helicopter was called to the area about 3.15pm after the pair became trapped while fishing.
A large swell prevented life boats from reaching the father and son, pilot Todd Dunham said.
An 18-year-old lifeguard showed extreme courage when she swam from a rescue boat to assist the pair and comfort them until the helicopter arrived, he said.
After the helicopter arrived at the scene the man and boy were winched to safety and flown to shore where they were checked for hypothermia.