Christchurch mayor Lianne Dalziel told Mike Hosking on Newstalk ZB this morning she was "very worried" for her city.
"We've been going through what's happened overnight. There's been more evacuations - we're looking at 450 properties approximately that have been officially evacuated, with police doorknocking and the army in support as well, so it is very serious."
She said people have been reporting seeing the fire very close to their properties near the Port Hills.
"It looks as if up to seven properties have been affected by the fire. It's difficult to say until light arrives, to get a full handle on how many properties have been destroyed."
Dalziel said the blaze was a "difficult fire".