The bridge that spans the Mississippi River from New Orleans to Gretna was one of the few ways out, until police from Gretna used force to stop pedestrians from crossing it. Since most of the police officers were white and most of the evacuees were black, the incident quickly took on racial overtones. 60 Minutes wondered why, under any circumstances, people who were only trying to walk out of a devastated city would be prevented from reaching relative safety.
Correspondent Ed Bradley went to New Orleans to find out. But, as with so many things in America, when it comes to race, the answer is hardly ever black and white.
The bridge where the incident took place is called the Crescent City Connection, linking the city of New Orleans with the west bank of the Mississippi River.
It was Wednesday, three days after Katrina had struck, when thousands of people started to walk across the bridge. Some 6,000 were put on buses. The exodus continued the next day when a group of tourists who had been staying in the French Quarter started heading in that direction.
Along the way, they were joined by hundreds of locals. But when this group tried to cross the bridge, they were met by a line of armed Gretna policemen who fired shotguns over their heads, told them Gretna was closed and turned them back.
60 Minutes found eight people who were on the bridge that day. Cathey Golden, who now lives in Boston, was visiting her hometown with her daughter, her son and three of their friends. Larry Bradshaw and Lorry Beth Slonsky, both paramedics from San Francisco, were in town for a convention. They all met the morning they were forced to leave the hotel where they had been staying since the hurricane.
"There was no electricity or plumbing and so after four days it just became, I'm sure, a danger to not just the hotel, for us! We needed to get out," remembers Slonsky.
They joined thousands of people who had been left behind in New Orleans and were walking the streets looking for help.
Two hundred people from the hotel ended up stranded across from the police department's command post.
"A gentleman came out and identified himself as one of the commanders. And he said 'I have a solution. I have buses waiting for you across the bridge,'" Bradshaw recalls.
With that assurance, they joined hundreds of other people who were walking toward the bridge to Gretna. Images taken that day by a CBS News crew driving across the bridge show groups of evacuees approaching a line of policemen holding shotguns. The police car was marked Gretna Police.
Cathey Golden told 60 Minutes that when her group reached the police line, they were told there were no buses, and stopped with a shotgun blast.
What was her reaction when she heard the gunshot?
"I was scared at first. I've heard gunshots before, because I live in an inner city area. But not a shotgun. And I was concerned about my safety and those who were with me," she says.
One of the people on the bridge with Cathey Golden was Shauron Holloman. She says she saw police officers fire their guns. "We were close enough to them. They'd rack their shotguns and let off a warning shot. We were this far away," Holloman says with a gesture. "This far away from you as I am," says Holloman.
Larry Bradshaw, who was at the front of the group, says he tried to get an explanation why they were being turned back.
"The only two explanations we ever received was, one, 'We're not going to have any Superdomes over here,' and 'This is not New Orleans,'" Bradshaw says. "To me, that was code language or code words for, 'We're not having black people coming into our neighborhood.'"
With nowhere to go, they set up a makeshift camp in the middle of the highway. The plan was to spend the night on the bridge and try to cross again the next day. But then a vehicle with Gretna police markings drove up.
"He sped down in his cruiser and over the loudspeaker he just continuously said, 'Get the f*** off the bridge,'" a male eyewitness who was on the bridge that day told Bradley. "And would point his gun at some people."
At that point a helicopter dropped close to the encampment and its downdraft blew things everywhere, forcing the evacuees off the bridge. They believe that the motive was racism.
Why does the eyewitness think they were turned away? "I think because the group was 95 percent African American," he says.
Asked if there was any evidence to support that, Shauron Holloman says, "A group of people trying to leave a city that's predominantly African American. And you have the officers who were white. That's the way it appears. And in that situation, that's the way you feel. We weren't given any information as to why we couldn't leave. So just appearance alone would make me feel that way."