A nanny accused of beheading a four-year old girl in her care and then setting the family's apartment on fire was formally charged with murder of a minor today in Moscow.

Gulchekhra Bobokulova from Uzbekistan has admitted to the crimes and told a Moscow court this week "Allah ordered me" to do it.

In an online video posted yesterday, she says: "I took revenge against those who spilled blood." The video was taken after she was arrested and it's not clear to whom she is speaking.

"Putin spilled blood, planes carried out bombings. Why are Muslims being killed? They also want to live."

Russia is supporting Syrian government forces with air strikes in their war against ISIS and al-Qaeda's Nusra Front.

Kremlin spokesperson Dmitry Peskov said yesterday: "You need to regard anything that such a deranged woman says accordingly."

On Monday, commuters were stunned when a woman appeared at a central Moscow Metro station dressed in a black abaya —  a loose black cape worn by some Muslim women — and brandished the severed head of a child.

Amateur video shows her yelling "Allahu akbar!" — Arabic for "God is great" — and "I am a terrorist." She made no attempts to resist when police tackled her, finding no explosives, before leading her away to detention.

Bobokulova had been working for a Russian family for three years as their nanny. She did not have a legal licence to work in Russia. 

Reports in Uzbekistan quote a family friend saying the 38-year-old has suffered from schizophrenia for more than a decade. 

The nanny's father told a Moscow newspaper his daughter was once admitted to a psychiatric hospital for two weeks and that before she left Uzbekistan, she'd been taking medication. 

'I am against advertising such an inhuman crime.' -Vadim Denging

The Russian family who employed her said they saw no problems prior to Monday and that she was "like family" to them.

Her gruesome story has given rise to a trail of dangling suspicions and anger. She's been dubbed the 'Bloody Nanny' by some media and online bloggers and has become a symbol for anti-immigrant voices who say Russia should crack down on unauthorized and undocumented immigrant workers. Estimates suggest more than one million immigrants work illegally in Russia.

The Communist party of the Russia Federation has drafted a stylized logo of a woman in black holding a head inside a red circle with a line through it, creating a proposed tool in their campaign to stop illegal immigration.

Main Russian television programs, even those focusing exclusively on crime, did not broadcast an amateur video showing the woman at the Metro station, stoking suspicion that the Kremlin was dictating the story be buried rather than give rise to comment that Russia's intervention in Syria is inciting repercussions domestically.


Flowers, toys and other items are placed to commemorate the child whose severed head was brandished by a woman outside the Oktyabrskoye Pole Metro station in Moscow on March 1, 2016. (Sergei Karpukhin/Reuters)

The deputy head of the parliamentary Committee on Information Policy said he was against using the tragedy as a tool for any politicking or even publicizing it.

"I am against advertising such an inhuman crime," Vadim Denging told the online news site The Daily Beast. "The story turned everything inside me upside down. For inhuman criminals like this woman, I would like us to have the death penalty."

People have been dropping flowers all week at the Metro station for the slain child.

Today at Friday prayers, Moscow's Muslims are gathering funds for the family of the child. The press service of the Spiritual Administration of Muslims says the campaign should be a "symbol of spiritual unity in the face of the family's  grief and [an incident] that shocked to the depths of Russian society." 

Bobokulova will remain under arrest for two months before sentencing.