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Storm Isaac picks up speed on its way towards the US

28 August 2012 Last updated at 23:02 BST

Residents of the US Gulf Coast are boarding up homes and buying in extra supplies as Hurricane Isaac bears down on the region.

The storm is likely to make landfall by Tuesday night and is expected to hit New Orleans - seven years after the much stronger Hurricane Katrina struck.

Alastair Leithead reports.