Samuel Little has confessed to murdering 90 women between 1970 and 2005.

Mark Rogers / AP

The FBI is asking for help identifying victims of one of the most prolific serial killers in US history, using drawings he made in prison. Samuel Little, 78, was convicted in 2014 of murdering three women in Los Angeles in the 1980s. Investigators used DNA evidence to bring him to justice, but they suspected he was responsible for killing dozens more women in cities across the country between 1970 and 2005. Little has confessed to 90 murders, and investigators have spent recent years trying to determine if his stories are true. So far, 34 murdered women have been tied to his claims, but many potential victims remain unknown. In 2018, he spoke at length with a New York magazine reporter about finding vulnerable women — involved in prostitution or drugs — and how he enjoyed hurting them. Because he knocked out and then strangled women, it's possible their deaths were not classified as murders, leaving no clear paper trail for investigators. But Little has spent his time in prison drawing, and on Wednesday, the FBI released 16 images in the hopes that a family member or friend will match a face or the minimal details Little has provided to a missing person. Anyone with information can contact 800-634-4097. Here are the women the FBI wants to identify:

Latina woman in her forties FBI

Little says she was killed in 1988 or 1996 in Phoenix, where she likely also lived. The FBI has not linked his confession to any known murder victim.

Ann, a white woman FBI

Little says she was killed in 1997 in Phoenix. The FBI has not linked his confession to any known murder victim.

Black woman, 28 or 29 years old FBI

Little picked the woman up in Memphis, Tennessee, in 1984. Little says she was killed across the river in West Memphis, Arkansas. The FBI has confirmed an unidentified woman's body was recovered at the time, matching Little's confession.

White woman, between 23 and 25 years old FBI

Little said he killed the woman in Los Angeles in 1996. The FBI has not linked his confession to any known murder victim.

Mary Ann or Marianne, 18 FBI

Little said he killed the black teenager in Miami in 1971 or 1972. The FBI has not linked his confession to any known murder victim.

Black woman, between 35 and 40 years old FBI

Little said he killed her in Atlanta in 1981. The FBI has not linked his confession to any known murder victim.

White woman, 26 years old FBI

She was killed in Atlanta in 1983 or 1984, and it's possible she was from Griffith, Georgia. The FBI has not linked Little's confession to any known murder victim.

Black woman, between 23 and 25 years old FBI

Little said he killed her in Atlanta in 1984. She was possibly a college student. The FBI has not linked Little's confession to any known murder victim.

Jo, 26 FBI

Jo, a 26-year-old black woman, was killed in Granite City, Illinois, between 1976 and 1979. Little said he met her in St. Louis. The FBI has not linked his confession to any known murder victim.

White woman FBI

Little said he met her in Columbus, Ohio, then killed her in Covington, Kentucky, in 1984. Her body was allegedly disposed of somewhere in northern Kentucky, but investigators have not linked Little's confession to any known murder victim.

Black woman, 24 FBI

The 24-year-old black woman was killed in Monroe, Louisiana, between 1987 and 1994. The FBI has not linked Little's confession to any known murder victim.

White woman, 20 to 25 years old FBI

Little says the woman was killed in 1972 in Prince George's County, Maryland. She was possibly from Massachusetts, and investigators have linked Little's confession to an unidentified murder victim.

Black woman, 35 to 45 years old FBI

Little said he met the woman in Gulfport, Mississippi, then killed her in Pascagoula, Mississippi, in 1977. It's possible she was from the area and worked at Ingalls Shipbuilding. The FBI has matched Little's confession to an unidentified murder victim.

Black woman, 40 FBI

Little said she was killed in 1993 in Las Vegas. The FBI has not linked Little's confession to any known murder victim.

Black woman FBI

Little said she was killed in 1976 or 1977 in Wichita Falls, Texas. He disposed of her body somewhere outside the city, but the FBI has not matched his confession with any known murder victim.

Black woman, 25 to 28 years old FBI