A DeKalb County man became the 11th person to plead guilty in a dog-fighting investigation that stretched from Georgia to Texas.

Edward Duckworth, 39, pleaded guilty to conspiracy Wednesday in federal court in Montgomery, Ala., said Assistant U.S. Attorney Clark Morris, who prosecuted the case.

Duckworth admitted to helping transport a dog from Georgia to Alabama for a dog fight in 2012. Georgia State troopers arrested him and his colleagues during a traffic stop when they were driving home. Troopers found a dead dog inside the vehicle.

He isn’t the only Duckworth to get wrapped up in the case. A few minutes after his plea, his mother, 61-year-old Mae Gussie Duckworth of DeKalb County, pleaded not guilty in federal court to a charge of threatening a witness in the case.

“If you are going to threaten a witness, not a good idea to do it on their voice mail,” Morris said.

Another defendant, Carlton Tippens of Riverdale, was also indicted in connection with transporting the dog to Alabama but prosecutors are dropping the federal charge, to have him instead prosecuted on a state charge in Lee County.

“I don’t think he was training dogs to fight,” Morris said. “It came to light that Tippens was attending a lot more than he was involved in fighting dogs. At the time he was arrested there was no federal law about attending a dog fight. There is now, but only since January.”

The multi-year undercover investigation involved federal, state and local police. It resulted in the seizure of 458 dogs in Alabama, Georgia and Mississippi, Morris said. The arrests and searches began last August in what animal rights groups described as the nation’s second largest dog-fighting investigation.

Morris said most of the fights were held in a wooded area near Auburn, Ala., owned by Donnie Anderson, 49, who pleaded guilty to one count of conspiracy, four counts of sponsoring dog fights, one count of possessing a fighting dog, and one count of operating an illegal gambling business in April.

He admitted dog owners and spectators bet on the matches he organized in the Auburn area from 2009 to 2013 and that one dog owner left a fight with $35,000 in cash, the Associated Press reported.

Bets on each dog fight could range from $20,000 to as high as $200,000, Morris said.

“Each side was betting $200,000,” she said. “If I have a great dog that I think can win these fights, then all my friends are going to bet with me.

“Most people working nine to five don’t have that kind of money,” she said.

According to court testimony, the crackdown grew out of a wiretap in a Georgia drug investigation where the suspect and Anderson had multiple conversations that often involved dog fighting, the Associated Press reported.

Auburn Police Detective Chris Carver testified in a court hearing last year that Anderson would hold fights on his rural property at night and people would pay $100 to $150 to attend. He said there would be two to five fights per night and Anderson would provide beer and hot dogs.

Investigators seized 114 dogs from his property, Morris said. More than $500,000 was seized during searches of 11 properties in Alabama and two in Georgia, she said.

Nine others from Alabama, Georgia, Mississippi and Texas have already pleaded guilty and are awaiting sentencing. They include Lawrence Watford, 35, of Adel, , who pleaded guilty in April to conspiracy. He admitted to training fighting dogs in Cook County and transporting them to Alabama to fight. He was arrested in Phenix City, Ala., on Dec. 3, 2011 with an injured dog.

They all face up to five years in prison. No one has yet been sentenced.