Semhar, of Ethiopian origin, was discovered in her Carouge home last Friday evening, an hour after cantonal police issued a bulletin about her disappearance.
Newspaper Le Matin is reporting that an Ethiopian friend of the girl’s single mother raped the girl before strangling her and hiding her beneath a bed in the apartment.
The newspaper did not cite any sources.
The girl’s mother had reported Semhar missing to police after she was last seen on Thursday evening with friends walking from the Drize school in Carouge.
Semhar’s body was found under a bed at her home by a police dog.
Le Matin reports that her 14-year-old sister and two-year-old-brother had been sleeping on the bed above the corpse.
As of early Tuesday, police, who say they suspect murder in the case, had not confirmed the report.
A police spokesman said that releasing any additional information risked harming the investigation.
Police have interviewed the man, who denies the allegations, according to the Tribune de Genève.
Investigators are conducting an analysis of DNA samples.
The results of an autopsy are expected to shed further light on the exact circumstances of the young girl’s death.