The 40-year-old man, Esmail Rangraz, allegedly confessed to the brutal murder after the body of the girl, Atena Aslani, was found in the garage of his house 20 days later.
Though Rangraz was not confessing to committing the crime for 14 days, eventually he showed the place where the body was.
Before the execution Rangraz told journalists that he killed the underage girl by accident, pleading not guilty.
As it became known during the investigation, Rangraz had raped two more women.
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