A German federal court said Friday it has rejected an appeal by a man who admitted killing and eating an acquaintance he met on the Internet against his murder conviction.

Armin Meiwes, a computer technician, was sentenced in May to life in prison after being retried and convicted for murder in a case that both fascinated and appalled Germany.

In his appeal to the Federal Court of Justice, Meiwes argued that the death of Bernd Juergen Brandes should be classified as a mercy killing.

The court "rejected the appeal ... as clearly unfounded," according to a statement Friday.

It noted that Meiwes' life sentence meant he could be released after 15 years at the earliest — "and then only if he is no longer dangerous."

Meiwes has said that Brandes traveled from Berlin in 2001 after answering his Internet posting under the pseudonym "Franky" seeking a young man for "slaughter and consumption." He said Brandes wanted to be stabbed to death after drinking a bottle of cold medicine to lose consciousness. Meiwes captured the killing on video.

Police tracked down and arrested Meiwes in December 2002 after a student in Austria alerted them to a message Meiwes had posted on the Internet seeking a man willing to be killed and eaten.

In early 2004, a court in the city of Kassel convicted Meiwes of manslaughter and sentenced him to 8 1/2 years in prison, but prosecutors appealed the verdict.

Federal judges overturned that ruling and ordered a retrial, arguing that the lower court, in rejecting murder charges, failed to give sufficient consideration to the sexual motive behind the killing.

Announcing the verdict after the retrial in a Frankfurt court, presiding judge Klaus Drescher last year described the killing as "a particularly perverse murder."

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