Dailymail cited a report on the newspaper France Soir by renowned investigative reporter Guilhem Battut as reporting:
Madeleine McCann
died from an overdose of sleeping pills, it was claimed yesterday.
French investigative reporter Guilhem Battut said a report outlining how the four-year-old met her death was already with Portuguese prosecutors.
The newspaper France Soir said it contains scientific analysis of the bodily fluids found in the boot of the car hired by Kate and Gerry McCann which "prove that the little girl had ingested medicines, without doubt sleeping pills, in large quantities".
Another development in the Missing Madeleine case is Kate McCann's diary' tells of struggle to control [hyperactive] Madeleine'. It supports theories published in Portugal that Mrs McCann was involved in Madeleine's death and her husband helped her dispose of their daughter's body.
Source: Madeleine 'was killed by overdose of sleeping tablets'