Hazardous bushfire smoke smothers Sydney

Australia's bushfires have blanketed Sydney in dangerous smoke - prompting extreme health warnings for the country's most populous city.

Officials said air quality in some areas was at 10 times hazardous levels on Tuesday (November 19).

Advice to residents was to stay indoors as much as possible.

One Sydneysider said it was - quote - the "worst we've ever seen it."

Wildfires have claimed at least four lives so far, destroyed more than 300 homes, and also put local wildlife at huge risk.

A woman on Tuesday endangered her own life to rescue a scorched koala in New South Wales - wrapping the animal in her shirt and cooling its burned skin and fur with water.

Strong winds have sparked more than 100 fires across the east coast.

The states of New South Wales and Queensland have been hit particularly hard.

But though Australia is prone to bushfires in its dry, hot summer climes, fierce blazes have come much earlier than expected - due to a long drought and soaring temperatures.

The current crisis has mostly been contained to the east coast so far.

But officials in South Australia warned on Tuesday that near-record temperatures have been forecast - raising the risks in that state too.