The smaller Chediski fire - started when an injured hiker tried to signal a helicopter for help - has merged with the Rodeo fire, which is also believed to have been started by man.

Firefighters' fears were realised and the two blazes became one (AP)

Twenty-five thousand people across the state have been evacuated

About 200 homes have been destroyed

The 8,000 residents of Show Low were evacuated at the weekend

Airtankers are dropping water and fire retardants on to the flames (AP)...

... while on the ground, firefighters are risking their lives

For much of the time, they are powerless in the face of this force of nature (AP)

The flames and smoke can be seen from space (AP)