Four children were assessed and treated at the scene.
It was initially reported, just after 4pm, up to six people were in trouble. Two rescue helicopters were dispatched, while police, St John and the Mangonui Fire Brigade also responded.
Mangonui Chief Fire Officer Antony Pedersen said the beach was busy at the time. Cable Bay was not known as dangerous, but choppy water and a strong wind may have generated an undertow on Tuesday.
It is understood that the father, his daughter and twin sons were holidaying in the Far North while the children's mother remained in Palmerston North.