US tornadoes, wildfires and dust storms leave 40 dead and 'staggering' damage

At least 40 people have died after tornadoes ripped through a swathe of the US Midwest and South.

Missouri bore the brunt of the twisters, which began to spawn on Friday. At least 12 people have died in that state.

Powerful winds in Texas and Kansas whipped up dust storms that resulted in vehicle pile-ups and a dozen deaths.