Which statement is not true?

Hurricane Katrina most likely killed thousands of people in New Orleans, Mayor Ray Nagin said Wednesday as conditions continued to deteriorate in the flood-ravaged city. "We know there is a significant number of dead bodies in the water and other people dead in attics," Nagin said. Asked how many, he said: "Minimum, hundreds. Most likely, thousands." There is no official death toll in New Orleans, as the city is focusing first on trying to save thousands of stranded residents. But Lt. Kevin Cowan of the state Office of Emergency Preparedness told the Associated Press that Nagin’s estimate was plausible. He said that be cause several thousand people have been rescued, it could be assumed there were lots of others who weren’t. "It’s already been several days," Cowan said. "You’ve had reports there are casualties. You all can do the math."