Ryan Johnston, 37, was sentenced at Inner London Crown Court on Friday to nine years in prison, with a further five on licence, the Crown Prosecution Service (CPS) said.

He was charged with rape, attempted rape and two counts of sexual assault, as well as outraging public decency in relation to another complainant.

Johnston chased two women to their home after they noticed him masturbating while looking through the window outside a house near Bounds Green Underground station at around 5am on 23 February 2020, the British Transport Police (BTP) said.

He banged on their door and put his hand through the letterbox after the women managed to get inside safely before he eventually left.

He then boarded a Piccadilly Line train at Heathrow Terminal Five around three hours later, where he approached a young woman who was asleep, the BTP said.

Johnston sexually assaulted and then raped the 20-year-old - who was returning home from an evening out with friends - in front of other passengers.

A French national travelling with his 11-year-old son witnessed the attack and reported it to the police.

But the attack was not captured on CCTV and officers were unable to identify the victim at the time of the attack, the BTP said.

Johnston was arrested at HMP Brixton - where he was serving time for burglary - in December 2022, after a BTP review of historical rape cases led to his identification, and detectives identified the victim in the same month.

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The French national was flown to the UK to testify at the trial, where he helped rebut Johnston's claims he knew the complainant and she had consented, the CPS said.

A jury found Johnston guilty of all five charges after a two-week trial at Inner London Crown Court in August.

He was also placed on the sex offenders register indefinitely.

Senior investigating officer, Detective Inspector Paul Attwell of the BTP's Major, Serious and Organised Crime Unit, said: "Johnston's brazen attack in front of witnesses highlights his lack of shame or remorse for his actions, something which continued throughout his trial.

"I am thankful his violence and despicable actions have been recognised by the guilty verdicts and significant sentence.

"His depraved actions will have a life-long impact on the victim and those who witnessed this.

"I am thankful for their bravery throughout this investigation. I hope they can now find some comfort in the fact justice has been served."