A stalker who carried out a knifepoint sex attack on a transsexual after she turned down his advances has been jailed for seven years, more than two decades after the attack.

Phillip Robertson, 50, of Holmewood Road, Streatham Hill, pestered his victim for days before sneaking into her flat through a kitchen window.

The victim, who is biologically male but lives as a woman, was brutally violated in 1990, but a police investigation at the time failed to find the attacker.

It is not known whether Robertson, who was arrested in January following a cold case review, knew his victim was a man.

Robertson was found guilty of buggery at an earlier trial.

The court heard Robertson, then 29, first slapped his victim’s backside as she walked home from a pub with friends on September 4, 1990.

He then followed her home before banging on the front door and asking her out on a date.

She refused, but Robertson sneaked in and bolted the front door shut. He then grabbed her, held a knife to her throat, and carried out the assault.

Robertson, who has previous convictions for wounding with intent, theft, burglary, and possession of class A drugs, then fled when her boyfriend returned and began knocking on the front door.

Abdel Sayed, defending, said Robertson’s family, his daughter and granddaughter, had not been told why he was on trial.

She said: “He is too ashamed to tell them of the nature of the offence.”

His victim, currently unemployed, battled with depression and suffered from heroin addiction following the attack, the court was told.

Jailing Robertson on Thursday, September 8, Judge Richard Hone QC said his actions were “cruel and inhumane”.

He said: "The humiliation, the degradation and the shame that you forced her to undergo cannot be understated.

"These were premeditated, brutal and callous acts even though the duration of the act was relatively short before her boyfriend knocked on the front door.

"What you did destroyed her relationship and also put a stop to the gender reassignment surgery for which she had taken treatment for several years."