A German woman is on trial over allegations she brutalized her boyfriend before decapitating him with a circular saw and disposing of the body.

The December 2008 killing came to light only last year when an acquaintance of the defendant went to police.

They found the body, which she and two friends had allegedly buried several years earlier, in the garden of her Munich home.

The 32-year-old, identified only as Gabriele P. in line with German privacy rules, went on trial for murder at the Munich state court on Monday, news agency dpa reported.

Prosecutors say she attacked her boyfriend, who was tied to a bed and blindfolded with blacked-out swim goggles, with the circular saw and decapitated him, probably after he died from wounds to the upper body.