MIAMI -- A woman who was notorious for her connection to cocaine and violent murders will be walking out of prison Sunday.

Griselda Blanco will be released, and then deported.

Blanco was the most infamous of the so-called "cocaine cowboys" who terrorized Miami in the late 1970s and early '80s.

Nelson Andreu is a retired Miami homicide detective who spent half of his homicide career investigating Blanco, who he says was tied to at least 20 murders.

"Her MO was to take care of business," Andreu said. "It was just to kill people."

Andreu says Blanco was one of the original cocaine cowboys -- responsible for bringing in tons of the drug during a violent era, a turbulent time that inspired the popular TV show, "Miami Vice."

The cocaine cowboys gained attention after the notorious Dadeland Mall massacre in July of 1979 masterminded by a machine gun toting Blanco, said Andreu. Four people died in the massacre.

"It was a turf battle -- a drug money battle," Andreu said. "It was one of those things where she (Blanco) didn't care who got killed."

Blanco was convicted of killing Alfredo and Grizel Lorenzo, a couple who owed money for drugs in 1982, and the horrifying murder of 2-year-old Johnny Castro. He was shot by mistake by a gunman aiming for the boy's father.

"The son was sitting by an armrest of the car and he got shot and killed after he was struck in the face," Andreu said.

Blanco was known as "La Madrina" -- the godmother of the cocaine industry.

"She was notorious. She would have you killed for a variety of reasons," Andreu said. "If she bought drugs from you and didn't want to pay you, she'd have you killed. If you bought drugs from her and didn't pay her, she'd have you killed."

Blanco is now 61.

Cocaine trafficking has taken its toll on Blanco's family, too. Three of her four sons have been killed.

Sunday, she finishes serving a 20-year sentence for the murders of the Lorenzos and Johnny Castro.

Andreu said he had hoped Blanco would have been given a longer sentence, but prosecutors had to strike a deal after complications arose in the case and charges against her were reduced to second-degree murder.

"She is going to be deported, fortunately, not left in the United States," Andreu said. "And I think she's going to face the fate of her sons and other family members who were part of that organization. I don't think she's going to last that long in Colombia."