Suspect 1: Vincent Tabak

Born in 1978, he would have been 28 years old, when Frauke was murdered. He lived only 150 miles away back then. He was convicted for abducting and murdering a 25 year old woman in 2010. Her sexually abused body was found on the side of the road, fully clothed, 2 weeks after her abduction. He is described as an intelligent loner. He graduated university in 2003 and shortly after became a PhD student. In 2008 he received his PhD in Architecture. His PhD project was named “User
Simulation of Space Utilisation”. I've read it. It's actually creepy. To summarize it: In order to find a smart way to design office buildings, they have to know, how many times the employees go to the bathroom and for how long (no kidding), or when they take their cigarette breaks. 
Here's the link of his "masterpiece":
https://pure.tue.nl/ws/files/3363389/200910371.pdf
From a scientific point of view his dissertation is half-baked garbage, absolutely useless. Could Frauke have been misused as a guinea pig by this handsome "genius"? He was into violent porn, as the police found out and
he will rot in a British prison cell for a few more decades, I guess. He tries to get appealed though, claiming that it was all an accident, but nobody believes him.

Suspects 2: Wilfried W., Angelika W.

In 2006 these two lived less than 10 miles outside of Paderborn. They both were later convicted for torturing several women in their house which led to the death of two of them. In 2012 they lured their victims into their home using personal magazine ads. Police found out that his cellphone pinged on several locations, where also Frauke Liebs cellphone pinged. He owned dozens of cars including motor homes. They also took their victims cellphones and forged text messages to send them to the victim's friends and families.

Suspect 3: Identity unknown

This computer generated picture shows another suspect. He approached and tried to rape a 25 year old woman in 2009 in a small town 15 miles south of Paderborn. The woman could free herself and ran away. Her description of the perpetrator led to this photofit you see on the left.

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