On 28 August 2005, Hurricane Katrina hit the American city of New Orleans with the force of a nuclear explosion.
A state of emergency was declared as flood waters reached heights of up to 20 feet. Residents were advised to leave, but many of them, overwhelmingly poor and black, did not have the means to escape and were left stranded for days.
The government - and then-President Bush - was embarassingly slow to react, and the city languished as aid failed to reach it for four days - previously unthinkable in the world's richest country.
Watch original British Pathe footage from the crisis, above.