New Orleans braced for Isaac

Tropical storm Isaac strengthened into a hurricane just off the US Gulf Coast as it churned toward landfall in the New Orleans area seven years to the day after the city was devastated by Hurricane Katrina.

Brandishing automatic assault rifles to ward off any threat of looting, the troops in military vehicles took up positions on mostly deserted streets.

Their arrival came as driving rain and stiff winds began battering the city’s iconic French Quarter and its boarded-up storefronts.