Los Angeles police detectives said Thursday they are investigating at least four missing persons cases as a result of publicizing photos seized from the South Los Angeles property of alleged "Grim Sleeper" serial slaying suspect Lonnie David Franklin Jr.

The Los Angeles Police Department was flooded with hundreds of phone calls, e-mails and other tips last month after detectives released photographs of the unidentified women that were found in a trailer and garage belonging to Franklin, who has pleaded not guilty to 10 killings in South L.A. over three decades.

Thus far, at least 53 women have been identified by LAPD robbery-homicide detectives who are continuing to receive information since going public with the approximately 180 images, including duplicates.

In all, 79 photos have been or are in the process of being removed from the LAPD website after the women in them were identified.

Police would not discuss details of the missing persons cases other than to say they involved women whose images were found among Franklin's possessions.

Franklin is accused of sexually assaulting and killing 10 African American women in South L.A. At the time of his arrest, last July, authorities found a disturbing trove of about 1,000 photographs and hundreds of hours of video of women.

Some of the images appeared to be innocent snapshots, but many showed the women in more risque poses. The materials spanned several decades, dating back to the 1980s, and included video and digital camera images, Polaroids, conventional prints and even undeveloped film.

The primary motivation for releasing the images was to find out whether the women were alive and well, said LAPD Det. Dennis Kilcoyne. But they also have received more than 200 tips that ultimately could prove important to the Franklin case.

Franklin's attorney, Louisa Pensanti, was critical of the LAPD for releasing the photos and said more than a dozen were relatives or friends.

Detectives said they were concerned about how the images should be presented to the public because of the explicit nature of the material and understood that their release could force the women to revisit encounters with Franklin from periods in their lives they would rather forget.

For that reason, the LAPD opted to release closely cropped versions of the images that show the women's faces. Detectives also wanted to be sensitive to the families of the 10 women Franklin is alleged to have killed. Before the announcement, police invited members of the victims' families to LAPD headquarters to view the images that would be released.

The original batch of images included at least one known victim whose family was unable to meet with investigators before their press conference.