Hurricane Isaac sweeps into the US mainland
Hurricane Isaac has made landfall in the US state of Louisiana.
Winds of up to 80mph (130km/h) are lashing the shore, and the storm is heading in the direction of New Orleans, exactly seven years after Hurricane Katrina.
President Obama has warned residents in the hurricane's path not to "tempt fate" and to heed evacuation warnings.
The BBC's Alistair Leithead is following events in New Orleans.