Double murderer David Fuller, 68, has pleaded guilty at Croydon Crown Court to 16 sexual offences relating to 23 dead women in mortuaries between 2007 and 2020.
He pleaded guilty to 12 counts of sexual penetration of a corpse and four counts of possession of extreme pornography.
Fuller, who beat and strangled Wendy Knell, 25, and Caroline Pierce, 20, to death before sexually assaulting them in two separate attacks in Tunbridge Wells, Kent, in 1987, was sentenced to a whole-life term last year.
He pleaded guilty to murdering Ms Knell and Ms Pierce, as well as 51 other offences, including 44 charges relating to 78 victims in mortuaries between 2008 and November 2020.
Fuller filmed himself abusing corpses in the now-closed Kent and Sussex Hospital and the Tunbridge Wells Hospital, in Pembury, where he had worked as an electrician since 1989.
Kent Police said an investigation had led to evidence relating to a total of 101 victims and the latest charges relate to the 23 remaining victims, all of whom were deceased adult women - 10 have not been identified.
Fuller pleaded guilty to:
10 charges under section 70 of the Sexual Offences Act 2003 relating to offences involving 10 identified victims;
Two charges under section 70 of the Sexual Offences Act 2003 relating to offences involving three unidentified victims;
Two charges under section 63 of the Criminal Justice and Immigration Act 2008 relating to the possession of extreme pornography in connection with 13 identified victims; and
Two charges under section 63 of the Criminal Justice and Immigration Act 2008 relating to the possession of extreme pornography in connection with 10 unidentified victims.
Mrs Justice Cheema-Grubb said Fuller, who appeared in court by video-link from HMP Frankland, must appear in person when she sentences him in the week starting 5 December, likely at the Old Bailey.
Prosecutor Michael Bisgrove said victim personal statements are being prepared.
"There are many family members of the victims who would like to attend court in one way or another, some of whom who would wish to read their victim personal statements to the court," he said.
The Government has announced an independent inquiry into how Fuller went undetected until being arrested for what have been dubbed the "bedsit murders" on 3 December 2020 following new analysis of decades-old DNA evidence.
Ms Knell was found dead in her Guildford Road apartment on 23 June 1987, while Ms Pierce was snatched five months later on 24 November outside her home in Grosvenor Park, with her naked body discovered in a water-filled dyke at St Mary in the Marsh on 15 December.
Police discovered a library of images of Fuller attacking corpses when officers searched his three-bedroom semi-detached home in the town of Heathfield, East Sussex, where he lived with his family.
The victims included a nine-year-old girl, two 16-year-olds and a 100-year-old woman.
Senior Crown Prosecution Service prosecutor Libby Clark said: "Fuller's actions were depraved, disgusting and dehumanising, on a scale that has never been encountered before in legal history.
"It was vital for us to bring these additional charges for the women we could identify, and those we sadly couldn't, to reflect his offending and bring justice for the families that we can.
"The horrors of this case will no doubt remain with everyone who has worked so tirelessly to bring the case to a close."
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