LAPD Working to Identify 35 Possible ‘Grim Sleeper’ Serial Killer Victims

The Los Angeles Police Department is still trying to identify 35 women who may have been killed by “Grim Sleeper” serial killer Lonnie Franklin, who was convicted and sentenced to death for 10 murders earlier this year.

Detectives found more than 1,000 photos and videotapes of women and teenage girls in the former sanitation worker’s garage and backyard camper days after he was arrested in South Los Angeles in 2010.

(Franklin’s case is the focus of the upcoming People Magazine Investigates episode “The Grim Sleeper,” which airs Monday night at 10 p.m. ET on Investigation Discovery.)

Of those, police could not identify 180 images and sought help from the public to find them. The photos showed women exposing their breasts or in sexual poses. Some of the pictures looked like the women were unconscious, asleep or dead.

With the public’s help, police identified all but 35 of the women.

“We don’t know who these women are,” LAPD detective Daryn Dupree told PEOPLE in 2015. “We want to make sure these women are okay.”

• For more on the case of the Grim Sleeper serial killer case, watch “The Grim Sleeper” on our 10-part true crime show, People Magazine Investigates, airing Monday night at 10 p.m. ET on Investigation Discovery.

Detectives are particularly interested in finding out the identity of the missing woman listed as No. 117 and No. 171 in the photos released by the police department.

Two photos of the mystery woman were found hidden in an envelope inside Franklin’s freezer in his garage. Inside the same envelope, detectives also discovered a photo of Franklin’s last known victim, 25-year-old Janecia Peters, who was found by a homeless man in a dumpster on January 1, 2007, as well as a school ID and a drivers license of two missing women who were last seen near Franklin’s home on 81st Street and Western Avenue in 2005.

“We think it was a trophy bag,” said Dupree. “We want to know if this person is still alive.”

Detectives also found jewelry and weapons inside Franklin’s home, including the .25 caliber pistol that Franklin used to kill Peters.

Franklin is currently in San Quentin State Prison.

WATCH: Three Things To Know About ‘The Grim Sleeper’ Serial Killer

Most of Franklin’s victims were shot with a .25-caliber pistol while others were strangled. Their bodies were discovered in dumpsters and alleyways along Western Avenue in South Los Angeles, an area known for its cheap motels, liquor stores, gambling parlors, auto salvage yards and storefront churches.

His youngest victim, 15-year-old runaway Princess Berthomieux, was found strangled in an alley in Inglewood in 2002.

Franklin, a former corporal in the United States Army, was finally caught through familial DNA testing after his 28-year-old son Christopher was arrested for carrying a weapon in the summer of 2009 and had to give up a DNA swab.

Once it was determined that Christopher was related to the killer, detectives followed the elder Franklin to a pizza place in Long Beach. As Franklin finished his meal, a detective who posed as a busboy collected a fork, two plastic cups, a plate and a pizza slice left by Franklin. A few days later, DNA taken from the pizza slice came back as a match to DNA found on Grim Sleeper victim Barbara Ware. Franklin was linked to the cases through DNA and ballistics evidence.

• Watch the People Magazine Investigates After Show, on the new People/Entertainment Weekly Network (PEN). Go to PEOPLE.com/PEN, or download the PEN app on Apple TV, Roku Players, Amazon Fire TV, Xumo, Chromecast, iOS and Android devices

After Franklin was arrested in 2010 as he walked out of the mint green home he shared with his wife of 32 years, police investigated more than 400 cold case homicides looking for additional victims. In 2011, investigators announced their belief that Franklin allegedly killed at least six more women in addition to the 10 women he was convicted of murdering.

People Magazine Investigates: The Grim Sleeper airs Monday night at 10 p.m. ET on Investigation Discovery.

If anyone has information about the women in these photos, please call LAPD Detective Daryn Dupree at 213-486-6869.