A murderer who killed a transgender prostitute has been given an indefinite jail term for raping another woman in Brighton five weeks earlier.
The Old Bailey heard Neil McMillan, 43, formerly of Bennett Road, Brighton, posed a serious future risk of carrying out "extreme sexual violence".
He was given an indeterminate sentence on Monday for raping a prostitute last September.
McMillan was jailed for life in June for the murder of Andrea Waddell.
McMillan, a satellite TV installer originally from Dumfriesshire, was jailed for at least 22 years for murdering Ms Waddell and setting fire to her flat in Upper Lewes Road in October 2009.
Sentencing McMillan for the rape, Judge Stephen Kramer told him: "You entered a sequence of behaviour involving offending against sex workers that rapidly escalated from rape to murder, over five weeks.
"You pose a future risk of serious harm, namely extreme sexual violence, and those most at risk are female sex workers."
During the Andrew Waddell murder investigation, detectives had found a bloodstained sock at McMillan's home.
Police took DNA from the sock and managed to trace the victim who had been raped.
The court heard the 27-year-old rape victim had gone to a hotel room where McMillan was staying, to collect money that he owed her, but he raped her.
The prosecution said his actions had "affected her badly".
After the sentencing, Det Ch Insp Adam Hibbert, of Sussex police, said: "Discovering the blood-stained sock and subsequently a victim of rape was a huge surprise to the investigation team, but thankfully we have been able to provide some sort of justice for the 27-year-old woman."
He said the sock was sent for DNA tests as soon as it was discovered.
When detectives traced and spoke to the rape victim, she disclosed she had been attacked shortly before Ms Waddell was killed, he added.
Mr Hibbert said: "This had not been reported to us. Working with the victim and CPS we gathered sufficient evidence to support this allegation and this resulted in McMillan's conviction.
"This conviction is an example of the type of individual McMillan is - a man who preyed on vulnerable women in the community."
Ms Waddell, who was born male but had undergone gender reassignment surgery, had been working as a prostitute when she was murdered.
During the trial, jurors were asked to consider whether McMillan killed her after discovering she was transgender, or because she was unable to perform sexually because of physical ailments after illnesses including fibromyalgia.
The court heard that McMillan, a satellite TV installer, strangled Ms Waddell while in a "worked-up and angry mood".