"They were just crossing the bar and the boat just went sideways and it just capsized.
"We just got them on our boards and made sure that they were all rescued and pulled the boat in.
"They were exhausted and pretty cold."
The boat flipped in the sea at Kairaki Beach, north of Christchurch. Photo / George Heard A police spokesperson said a boat capsized but all on board made it back to shore safely.
A St John Ambulance spokesperson said they were notified of a boating incident in Waimakariri and sent two ambulances to the scene.
"We assessed and treated two patients with minor injuries at the scene," said the spokesperson.
The upturned craft was left on the shore with the surf crashing around it while the boaties were treated by medics.