Rewards offered as suspicious bushfires burn through WA's Kimberley

Bushfires have swept through more than a million hectares of bushland in far north Western Australia, with authorities hoping to flush out those responsible for a number lit deliberately.

A fire stretching between Waterbank and Willare, between Broome and Derby, has burned through more than 200,000 hectares.

Flames came close to the Thunderbird mine site last weekend, and WA's Department of Fire and Emergency Services said it was one of a number of the blazes believed to have been deliberately lit.

"Unfortunately it is a factor we need to address in the Kimberley region, arson is an issue," DFES Kimberley Superintendent Glenn Hall said.

"I can only encourage the public, if they see any suspicious activity to report it."

Derby detectives said on Friday they were investigating a series