Updated

The son of a 91-year-old woman who died in her wheelchair while waiting to be rescued from the city's Convention Center in the aftermath of Hurricane Katrina sued the city and state Thursday.

Herbert Freeman Jr.'s lawsuit accuses numerous state agencies and the city of New Orleans of "gross negligence and willful misconduct" in the death of his mother, Ethel Freeman. It was filed in state Civil District Court in New Orleans.

He plans to file a second lawsuit in federal court against the Federal Emergency Management Agency.

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The Convention Center had been overwhelmed with desperate evacuees, many of the elderly or ill. After she died, Ethel Freeman's body was pushed to one side and covered with a poncho.

Her son's lawyer, John Paul Massicot, said Ethel Freeman had been instructed to go the fetid Convention Center.

"Let's not forget, she survived the storm. The storm didn't get her. She didn't survive the rescue," Massicot said.

The woman and her son got caught as water began to rise in their neighborhood, the lawsuit said. The day after the storm made landfall, breaking New Orleans' weak levees, the son was able to secure a boat and place his mother inside, still sitting in her wheelchair.

New Orleans Police instructed them to seek shelter at the Convention Center, where they were told buses would pick them up, the lawsuit states.

At the shelter, they found teeming crowds and no food, water or buses. As his mother began to slip away in the suffocating heat, Freeman pleaded for medical help, but there was none. She died 24 hours after reaching the convention center.

For four days, Freeman watched over his mother's body before being ordered to leave at gunpoint after buses finally arrived, said Massicot. He recalls kneeling by the wheelchair and praying, then leaving a note with his address and phone number inside one of her pockets.

It would take him seven weeks to track down her body, which was taken to a morgue in St. Gabriel, La.

The lawsuit charges that even though a mandatory evacuation was called, it was announced only 20 hours before the storm made landfall, not enough time to evacuate a chronically ill woman.

State officials said they were not prepared to comment on the lawsuit. City officials did not return calls or an e-mail seeking comment.