Approximately 10,000 gallons of crude oil has leaked onto the streets of Los Angeles after a high-pressure pipe burst.
It is believed to have covered a half-mile area and is knee deep in some areas.
Locals have tweeted pictures of the flowing oil on the streets:
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The couple were also introduced to their namesake koalas during day of their tour.
Fans were eager to catch a glimpse of any baby bump.
The duke is to recognise the group’s ‘extraordinary contribution’ during a reception at Buckingham Palace.