High winds have whipped the Christchurch Port Hills fires into one big raging inferno, prompting a state of emergency to be declared for Christchurch City and Selwyn District.

Eight properties are believed to have been damaged by the fire and about 1800 hectares of land has been scorched. Roads are closed and power is out in some parts of the city.

The devastation follows the death of pilot David Steven Askin, 38, who was battling the blaze from the air on Tuesday when his helicopter crashed near the Sugarloaf car park.

A total of 450 properties have been officially evacuated, with police door-knocking downhill of the Sign of the Takehe as far as Kiteroa Place since early this morning. Others have self-evacuated as the fire spread overnight. Evacuations are continuing on the Port Hills as the fires continue to burn.

In addition to the Christchurch fire ban, a total fire ban is now in place from South Canterbury through to the north end of the Hurunui District.

Christchurch Civil Defence Controller David Adamson says there has been a phenomenal amount of ground staff working through the night, with additional crews added from day break.

'The fire now spans a large front and all agencies are coordinating very well to fight the blaze and support the community.

'However, the situation remains very serious. Police and the Defence Force have had a huge job overnight with evacuations, the setting-up of cordons around key areas and security patrols of areas that have been evacuated.”

The police are stressing that it is imperative that members of the public keep away from the hills. People 'rubber-necking” are disrupting the emergency response and making it harder for police and fire services to do their jobs.

The public are encouraged to follow official updates on the Christchurch City Council's Newsline website and social media, as well as other emergency services updates.

Welfare centres are operating at Halswell Library and the Nga Hau e Wha Marae for evacuated residents. Anyone who is not able to evacuate by themselves should call 111. The Ministry of Education has confirmed that both Governors Bay School and Cashmere Primary School are closed today.

The risks of smoke inhalation has prompted a health warning from the Canterbury District Health Board.

People who have difficulty breathing, have a prolonged cough or tightness in their chest should contact their GP or phone 111 if it is an emergency.