ELEVEN years after her murder, Simone Strobel's parents are still desperate to know what happened to their daughter.

Simone's parents have not lost hope that the mystery surrounding the death of their daughter would still be solved, with Gabi Strobel telling German news outlet Stern: "It's just a call to those who know more what happened that night and deliver us from this agony of reflection and brooding." (Translated from German)

Simone, a 25-year-old German backpacker and kindergarten teacher arrived in Lismore on February 11, 2005.

She was reported missing the following morning and her body was found six days later, concealed in long grass and palm fronds next to the old bocce club in Uralba St.

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Nobody has ever been charged with her murder, yet the case has attracted interest across the world.

Simone had been travelling with her boyfriend, Tobias Suckfuell, his sister Katrin Suckfuell and friend Jens Martin, and Tobias was later named the prime suspect by German authorities.

A subsequent inquest at Lismore, which Tobias and Katrin refused to attend, heard circumstantial evidence suggesting he murdered Simone by suffocating her with a pillow and then, possibly with Katrin's help, carefully concealed the body under palm fronds in the nearby bocce court.

If anyone has any information regarding the death of Simone Strobel in 2005, they should contact police.