At least 70 large wildfires burning in US west as fears mount over conditions

Bootleg is now the largest US forest fire at 281,208 acres and just 22% contained as excessive heat' forecast

At least 70 large wildfires are burning across the US west and nearby states - engulfing more than 1m acres in flames - as fears mount that shifting conditions can worsen an already dire situation. Significant areas of these states are in the grips of drought conditions that are considered extreme" and exceptional" - the most severe categories.

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