Investigators unable to tell how fire on Port Hills broke out

Fire investgators said last summer's huge fire on Christchurch's Port Hills started on private property but they've been unable to determine how it broke out. The wildfire started near the a walking track back in February and spread over 700 hectares, forcing the evacuation of more than 100 properties.The blaze triggered a major firefighting operation including more than 100 firefighters, 15 helicopters, two fixed-wing aircrafts and almost 30 fire engines. Local residents who nearly lost their homes in the blaze remain wary of further fires in the area, reporter Adam Burns has more.