Police are currently investigating the Madeleine McCann suspect over a separate child sex allegation just weeks before she vanished in Portugal.
The German drifter Christian B is suspected of grabbing a 10-year-old girl and performing a sex act in front of her on Salema Beach in April 2007.
Salema Beach is around a 15-minute drive from Praia da Luz, where Madeleine disappeared from a holiday apartment on May 3.
German prosecutor Hans-Christian Wolters, who is investigating Christian B in the Madeleine case, said: "In this case of 2007 he is suspected of showing himself in a sexual, offensive way in front of a 10-year-old German child on a beach.
“I cannot say exactly if he was masturbating in front of the child or if he has just shown himself naked.
"In Germany that is a sexual abuse of a child - and that's why we are investigating. But he is just a suspect, we haven't charged him, so I cannot say anything about how this investigation will end.
"What I can say is that Christian B knows about this second investigation - we sent his lawyer the files of this case."
German judicial authorities were made aware of the incident last year through a survey of sexual offences from Portugal.
sonos sonos One (Gen 2) - Voice Controlled Smart Speaker with Amazon Alexa Built-in - Black read more
The girl, who has not been named, was playing with other children during a trip to the breach with her family when a naked man grabbed hold of her.
She was saved when adults rushed to her aid, with the suspect fleeing from the scene after being chased by her father.
The original investigation was closed without a suspect, but reopened when the girl’s mother contacted police after Christian B was identified as a suspect in the Madeleine case.
Mr Wolters said: "Of course we are looking for other crimes related to Christian B. And if we have any findings we will start new investigations.
"You have to look at these things detached. A concrete connection between this crime, even with this new child abuse, and even if it was in the year 2007, but there is no direct connection to the Madeleine case except that the suspect is Christian B."
The 43-year-old is currently inprisoned in Germany after being convicted of rape and drug traficking. He denies any involvement in the disappearance of Madeleine.
Christian B, as he is known in the German judicial system, lived on and off in the Algarve between 1995 and 2007.
all right reserved for yahoo news