Lonnie Franklin Jr., the alleged Grim Sleeper, is suspected in the deaths of eight more women

Last summer, when they caught the man believed to be the Grim Sleeper serial killer, Los Angeles police detectives assigned to the case knew their job was far from over.

They had tied Lonnie Franklin Jr. to the killings of 10 women in South L.A. during a period that spanned more than two decades. More work, however, was needed to answer the troubling questions that remained: Had he killed others? If so, how many? Who were they?

On Tuesday, after months spent combing through dozens of unsolved homicide files, countless missing person reports and eerie photographs of women found at Franklin’s residence, police went public with suspicions that eight additional women may have been his victims.

Franklin, 58, was indicted by a grand jury last month in the 10 slayings to which police say he is linked through a combination of DNA and ballistics evidence. Franklin has pleaded not guilty and remains in custody awaiting trial.

He is accused of killing seven women between 1985 and 1988 and three between 2002 and 2007, earning him the Grim Sleeper moniker from the L.A. Weekly newspaper because of what appeared to be a period of inactivity separating the killings. Throughout the investigation, however, police have been openly skeptical of the idea that the slayings stopped during the 13-year gap.

It was far more likely, they said, that Franklin killed others who were not linked to him or whose bodies were never recovered. He targeted women on the margins of society — many of them drug addicts and occasional prostitutes, police allege. Moreover, the bodies of several of his suspected victims were found in trash bins and Franklin worked as a garbage collector in the 1980s, raising the prospect that bodies of other victims could have been dumped in landfills and never found, police have said.

Two of eight women discussed Tuesday disappeared during the 13-year period. A third went missing in 1982, before the first of the 10 known killings.

No physical evidence implicates Franklin in any wrongdoing related to the eight additional women. By going public, police said, they are hoping people with information about the women will come forward either to eliminate them as potential victims or help confirm the detectives’ fears.

Of the eight women discussed Tuesday, three are of particular concern: Ayellah Marshall, a high school senior when she disappeared in 2005; Rolenia Morris, a 25-year-old who also was reported missing in 2005; and an unidentified woman whose photograph was found at Franklin’s residence when he was arrested.

Police discovered Marshall’s Hawthorne High School identification card, Morris’ Nevada driver license and photos of Morris in “compromising positions” and a photo of the unidentified woman in a refrigerator in Franklin’s garage, said LAPD Det. Dennis Kilcoyne, who heads the investigation into Franklin.

In the refrigerator police also found photos of Janecia Peters, one of the 10 women Franklin is accused of killing, as well as a photograph of another person, but that one was too dark to be of any use in the investigation.

Kilcoyne said investigators fear the cache of items and images found in the refrigerator was of special significance to Franklin, because he kept it separate from photographs of scores of other women found elsewhere in his residence, which he shared with his wife. Police have said Franklin’s wife has refused to talk to them.

“We hope for the best,” he said. “We wish nothing more than to find them alive and well, but the circumstances are gloomy.”

In addition, the families of four other missing women approached police after Franklin’s arrest, concerned about the possibility that they were victims, Kilcoyne said. Those women, according to Kilcoyne, lived lifestyles similar to those of the confirmed victims, including drug use and occasional prostitution. They also were known to frequent Franklin’s South L.A. neighborhood at the time they disappeared, Kilcoyne said.

Detectives believe Inez Warren, who was killed in 1988, may have been a victim of Franklin because her killing has similarities to the others Franklin is accused of committing. Like many of Franklin’s suspected victims, Warren was known to use drugs and turn occasionally to prostitution, and her body was found in an alley off Western Avenue with a single gunshot wound to the chest from a small-caliber handgun.

Detectives had previously suspected Franklin in another unsolved murder but have since dismissed the possibility, Kilcoyne said.

Also on Tuesday, Kilcoyne once again displayed 55 still photos of women that were found at Franklin’s home. They were part of a larger collection of photos that police released to the public in hopes of identifying the women and tracking them down or adding them to the list of possible victims. The 55 women remain unidentified.

joel.rubin@latimes.com