NEW ORLEANS -- An Orleans Parish grand jury declined Tuesday to indict a doctor accused of killing patients in the aftermath of Hurricane Katrina.

Last year, state Attorney General Charles Foti claimed Dr. Anna Pou and two nurses of killed four people with a "lethal cocktail" at Memorial Medical Center, reported WDSU-TV in New Orleans.

The four were among at least 34 who died at the sweltering, flooded hospital in the days after the August 2005 storm.

Orleans Parish District Attorney Eddie Jordan's office declined to prosecute nurses Lori Budo and Cheri Landry after they testified in the investigation.

The four Pou was accused of murdering ranged in age from 61 to 90 years old.

The attorney general said the four would have survived if they hadn't been given central nervous system depressants.

Pou, who has been free on bond, was never formally charged.

Supporters rallied for Pou late last week, and the doctor filed suit against the Louisiana attorney general on Monday.

In the lawsuit, she accuses him of using her arrest to fuel his re-election bid.