Portuguese police have reopened their investigation into the unsolved rape of an Irish woman after 16 years.
Hazel Behan, 37, believes her attacker may have been drifter Christian B, the main suspect in the disappearance of Madeleine McCann .
He was convicted of a similar rape a year after Ms Behan was attacked and two years before Madeleine vanished.
This week detectives collected their own archived case files from the court in Portimao to see if they could build a case against the suspect.
One problem they will face is that vital forensic evidence with potential DNA was destroyed on the orders of a judge, a common practice in Portuguese cases where no suspect is identified.
A source told Sky News: "Detectives are looking again for new evidence and the investigation is reopened."
Ms Behan was a 20-year-old holiday rep who arrived in Praia da Rocha on the Algarve coast in April 2004.
Two months later, a masked man climbed the balcony to her apartment and attacked her as she slept in the early hours.
He held a knife to her throat, tied her up and gagged her, then raped her repeatedly.
During the attack he threatened to kill her and left her bleeding before fleeing over the balcony.
Last month, when German drifter Christian B was named as the main suspect in the Madeleine case - and Ms Behan read about his conviction for raping an American woman in strikingly similar circumstances - she contacted the Scotland Yard Madeleine squad.
She told the Guardian newspaper: "My mind was blown when I read how he had attacked a woman in 2005, both the tactics and the methods he used, the tools he had with him, how well he had planned it out.
"I puked, to be honest with you, as reading about it took me right back to my experience."
Scotland Yard detectives interviewed Ms Behan and later told her they had contacted Portuguese police. It appears that has prompted the reopening of her case.
She has said she was badly treated by the Portuguese detectives, who abandoned their investigation after eight months without identifying a suspect.
Ms Behan described her attacker as white, slim, with blonde hair, blue eyes and possibly German.
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According to the case files, detectives were unable to find anyone in their records who matched the description, but that was wrong.
In another Portuguese police file seen by Sky News, there are photographs of a young Christian B who does fit the description.
They were taken by police in 1999, five years before Ms Behan was raped, after he was arrested and deported to Germany for child sex crimes.
If police do find evidence against Christian B for Ms Behan's attack it is unlikely he would be charged as Portugal has a 15-year statute of limitations on rape investigations.