A navy damage control team has boarded a burning ocean-going tug off Northland hours after the crew abandoned ship when fire broke out in the engine room.

An explosive device found in a car in south Auckland last night was like "a home made firecracker", say police.

A Rotorua man is alive today only because a stranger kicked down the door of his burning home and dragged him to safety.

A fire at an Auckland primary is the second major school fire in the upper North Island in two days, after arsonists torched classrooms at Kerikeri High.

Staff at Kerikeri High School fear students' mid-year exams and assignments may have been lost in a suspicious fire.