Bryan Vernon and Dorthy Bell are rescued from their rooftop after Hurricane Katrina hit, causing flooding in their New Orleans neighborhood

Authorities are continuing emergency rescue efforts after Hurricane Katrina slammed the Gulf Coast of the United States.

Mississippi Governor Haley Barbour says the death toll could be as high as 80 in one Mississippi county alone.

The powerful storm cut a path of destruction through (the southern U.S. states of) Louisiana, Alabama and Mississippi, uprooting trees and destroying homes and buildings.

Rescuers used helicopters to pluck stranded residents from rooftops of houses submerged in flooding. The death toll is expected to rise.

Live power lines are down and gas lines ruptured, and authorities are warning residents not to return to their homes yet.

The storm came ashore early Monday and has cut power to more than one-million residents. Officials say it could be weeks before residents are allowed back into the area.

Forecasters say the storm is now centered in northern Mississippi, and moving northeast.

Some information for this report provided by AP.