LARRY Murphy, the main suspect for the murder of three women here, has made friends with an Irish double rapist in Amsterdam.
The Dublin man, who cannot be named for legal reasons, raped two women at knife point in the south of the city more than 10 years ago.
The two men became "close pals" while they were both serving time for their crimes in Arbour Hill Prison in Dublin, which houses the country's sex offenders.
Murphy served a sentence for the rape of a young woman from Carlow and was about to murder her when he was interrupted by hunters.
Our photos show Murphy with the other Irish man in Amsterdam where Murphy tried to interact with female passers-by.
A garda source told the Irish Independent: "The man you have photographed with Murphy is a total brute just like his friend. He carried out a horrific attack on those two women.
"And like Murphy he had not come to garda attention before that event."
Security sources have described the attack by Murphy's friend as "absolutely horrific".
He held the women hostage in an apartment and attacked them with a knife.
He then took turns raping both of them, but was arrested soon after by uniformed gardai from Tallaght station.
Like Murphy, the Dublin man admitted his crimes – but offered no explanation for his savage act.
In October 2002 he was jailed for 10 years after pleading guilty to four counts of rape.
It is understood he is on the sex offenders' register, which had come into existence six months before his conviction in the Dublin Central Criminal Court.
The double rapist, who was released in 2008, kept in touch with Murphy who was himself released in August 2010.
But it wasn't discovered that the two men are now effectively living together until Murphy was tracked down to Amsterdam as part of a special investigation for the Irish Independent.
It is understood Murphy helped his friend get a job at the same logistics firm in May.
The double rapist collects Murphy for work every morning at 4am on his scooter.
And whenever the suspected serial killer goes out, he travels with his friend on the bike.
The men are rarely seen apart, and seem to spend all their free time together.
They were seen going fishing together, and the man regularly spends the night in Murphy's flat, which is situated in a quiet suburb where no one is aware of their sordid past.
The chilling revelation that Murphy's closest friend is also a dangerous rapist will be a source of grave concern to police.
Sources in Holland have confirmed that the Amsterdam police "are aware" of the presence of the two men in the city. A security source described the revelation by the Irish Independent as "very disturbing".
"If the only company Larry Murphy keeps is also a violent sex offender then it is hard to see how either of them has reformed. They should be kept under very close supervision."
Murphy has been living in the European sex and drugs capital for more than a year.
He only spent three weeks in Ireland since his release from prison despite reported sightings in practically every county in Ireland.
Murphy has told probation workers and gardai that he has no intention of ever coming back here because he fears for his safety.