Moscow investigators said Thursday that a nanny accused of decapitating a child has been diagnosed schizophrenic, as footage emerged of her apparently linking the killing to Russia's bombing in Syria, AFP reports.

Suspect Gyulchekhra Bobokulova from Muslim-majority Uzbekistan - whom the press have dubbed "the bloody nanny" - was detained on Monday as she was waving the child's severed head outside a metro station in northwestern Moscow. She was sent for psychiatric examinations.

Arriving at a Moscow court on Wednesday, the 38-year-old told journalists that "Allah ordered" the killing as a judge ordered her held in custody for two months over the murder of the girl, whom investigators say was aged either four or five.