Premier Steven Marshall says a person died in the Charleston area of the Adelaide Hills where the most significant fire continues to burn.
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It follows the death of a man in a road crash at Lameroo, which sparked a fire there while noted SA horse trainer John Glatz is in the Royal Adelaide Hospital with significant burns suffered while trying to protect his Adelaide Hills property at Woodside.
As well as the 15 homes destroyed across SA, 28 other buildings have also been lost along with 16 cars.
“My fear is this is only the tip of the iceberg. We haven’t had a chance to get back in to assess the damage,” Mr Marshall said.
“We know that in addition to the buildings and vehicles lost there are very significant losses in terms of livestock, animals, crops, vineyards.
“It is going to be a real scene of devastation, especially for those people in the Adelaide Hills who have been most affected.”
Authorities have also confirmed that 23 firefighters and several police have suffered injuries, including one firefighter who remains in hospital in a serious condition.
Three Country Fire Service trucks were also destroyed.
Police have confirmed they are currently checking on the welfare of 90 to 100 people across the various fire grounds.
On Friday’s day of catastrophic conditions more than 100 fires broke out before midday and have since destroyed about 40,000 hectares.
The remaining fires of most concern are the blaze in the Adelaide Hills and one burning along the north coast of Kangaroo Island.
Both are uncontrolled with fire crews and water bombers working to protect assets and establish control lines.
This latest fatality comes after two volunteer firefighters tragically lost their lives while battling a firestorm southwest of Sydney on Thursday.
Geoffrey Keaton, 32, and 36-year-old Andrew O’Dwyer were remembered as committed family men on Friday.
The two have been hailed as heroes as NSW residents prepare for a day of “catastrophic” fire danger which is almost certain to raze more homes.