The 19-year-old victim had called him using FaceTime after realising she was being followed. It meant that although he was left powerless to halt the attack he was able to capture a screenshot image of her attacker stamping on his girlfriend moments before raping her. The evidence was enough to put Portuguese-born Samuel Fortes behind bars for life this week.
Leeds Crown Court heard how Fortes, 27, followed his victim through the centre of the city in the early hours of Saturday, June 23, last year as she walked home after a night out.
The victim's boyfriend saw the beginning of her 15-minute ordeal before Fortes smashed her mobile phone, cutting off the footage. He dialled 999 to alert the police.
Fortes, who had travelled from Sheffield to cruise Leeds's bars, fled, hiding for two hours in a bush before catching a train home.
But he was identified after a single strand of his hair was discovered entangled in the hair of the victim. It revealed his DNA, which was known to police following previous convictions for domestic violence and carrying a knife.