Torrential rain and intense winds blasted Louisiana as Hurricane Gustav neared New Orleans and the Gulf Coast yesterday after forcing nearly two million people to flee.
New Orleans was locked down and streets completely empty as emergency workers who remained behind hunkered in safe buildings on high ground.
Power went out for many areas of coastal Louisiana, according to media reports, with rains that witnesses described as "horizontal". With landfall imminent, police and national guard deployed to New Orleans to prevent looting also pulled back off the streets for safety.
At 8:00 am (1300 GMT) the eye of the Category Two storm was just southwest of Grand Isle, Louisiana, and 80 miles (150 kilometers) south-southwest of New Orleans, pummelling the marshy Mississippi river delta coastline with winds of 110 miles (175 kilometers) per hour.
Despite a slight weakening of Gustav as it neared the coast, forecasters warned of an "extremely dangerous" surge of up to 4.2 meters (14 feet), not as high as earlier predicted but still enough to worry locals after Hurricane Katrina burst New Orleans' levees in 2005 and flooded the city for days.
Fearing a repeat of the Katrina disaster, thousands of troops, emergency workers and National Guard troops were positioned in New Orleans after what is being called the biggest evacuation in US history.
Three critically ill people were reported to have died as they were being moved from the danger zone.
Oil production in the crucial US oil-and-gas region was shut down, the Republican party suspended the start of its presidential election convention and President George W. Bush headed for Texas to monitor emergency preparations for Gustav, which has killed more than 80 people in Dominican Republic, Haiti and Jamaica.
Louisiana officials said there were about 750 National Guard troops in New Orleans if a new rescue operation was needed. Mayor Ray Nagin on Sunday ordered a curfew and vowed to throw looters into prison.