A rejected asylum seeker living in Germany has been jailed for 11-and-a-half years after he raped a young woman at knifepoint in front of her boyfriend.

The Ghanaian known only as Eric X, due to the country's strict privacy laws ,was convicted of raping a 23-year-old woman in a campsite in the Siegaue Nature Reserve campsite, near Bonn.

The 31-year-old threatened the woman and her 26-year-old boyfriend with a machete during the attack, in a campsite near the city on the Rhine, in April this year.

The court heard how the defendant entered the tent and told the boyfriend to remain where he was then X dragged the girl a few yards into a meadow, where she was raped.

The Daily Mail reported that X was branded highly dangerous by a psychiatric expert at Bonn State Court.

X had denied raping the woman but an expert said the chance of someone else's DNA being on the victim was a 30 billion to one chance.

X said: "If the court says the DNA fits, then I have to call the girl a prostitute. Anyone who supports this girl who claims to have been raped is the dirtiest person on earth."

The defendant was also found guilty of stealing a speaker and six euros from the couple.

The court heard how Just days before the horrific rape, X had was told by German authorities that he was to be deported to Italy, where he had first entered the Schengen zone.

The case sparked outrage in Germany as it emerged that when the boyfriend called emergency services the operator said "You are not f***ing with me I hope?" in disbelief that the rape was even happening.

After the assault had finished and the boyfriend gathered her up and began walking with her along a main road looking for help, he called police a second time.

Officers were again were not convinced by the man's claim and nearly 30 minutes later, officers arrived and the victim was taken to hospital.