"Because of (the detectives') hard work, I stand before you to announce the arrest of a suspect who has terrorized our community for far too long," said Mayor Antonio Villaraigosa during a news conference.
Franklin, 57, was arrested in front of his South Los Angeles home on the 1800 block of W. 81st Street on Wednesday. He is accused of killing 10 people from 1985 to 2007.
Los Angeles Police detectives linked Franklin to the crimes using DNA taken from his son after an arrest in an unrelated case. Based on the DNA found on Franklin's son, the "Grim Sleeper" suspect had to be a father or brother. Detectives then collected DNA evidence at a restaurant frequented by Franklin.
"We had surveillance follow him into a restaurant, and we had one of our surveillance detectives act as a bus boy, and he collected forks, glasses, napkins and yes, one piece of pizza crust," said Kilcoyne.
Officials say this is the first time a familial DNA search has been used successfully in the state. According to LAPD Chief Charlie Beck, the resources spent investigating the cases far exceeded any other case currently on their docket.
"This is a landmark case," Beck said. "This will change the way policing is done in the United States."
Franklin was charged with 10 counts of murder, one count of attempted murder, and special circumstance allegations of multiple murders, according to the L.A. County District Attorney's Office. Franklin would be eligible for the death penalty if convicted.
"Relief after about 22 years, big relief," said Mary Alexander, mother of one of the victims. "Makes me happy inside." Asked what she would like to see happen, Alexander said, "I'd like to see him get the death penalty. Most definitely. Because he just doesn't know how he's damaged so many lives."
The victims, ranging in age from 14 to 36, were shot, strangled or both, usually after some kind of sexual contact. Ten victims were women and several were prostitutes. One victim was male. All resided within Los Angeles County.
Janecia Peters was the last known victim. Peters' aunt Diane McQueen says she had lost hope that her niece's murder would ever be solved.
The 25-year-old woman in a crumpled photo held by McQueen was found shot to death in an alley in 2007.
"We miss her a whole lot and we're so glad that this day finally came," said an emotional McQueen. "It didn't seem like this day would ever come, but it did."
Neighbors said they thought Franklin was just a friendly neighborhood auto mechanic. Glenn Williams, who runs an auto parts store on Western Avenue, said Franklin was a good customer.
"He seemed like a very nice guy and he was a very helpful guy," Williams said. "It's amazing. He came to me every day, he knows all my children and everything else. It never dawned to me that he's that kind of person."
Franklin was employed by the LAPD 77th Division in 1981 for 18 months as a gas-pump attendant before he left that job to work for the L.A. Bureau of Sanitation. He has since been working as a private mechanic.
Police said that none of the "Grim Sleeper" murders they are investigating occurred during the time that Franklin worked for the LAPD.
Police said there may be more victims.