A 42-year-old grandmother who killed her grandchildren because she thought “they were possessed” by demons has been sentenced to 16 years in prison.

Svetlana Muradyan and her lover were caring for Vladislav Eliseev, 5, and his sister Esenia, 3, when they began to hallucinate during a drinking session in Belgorod region of Russia.

Mirror reports that the drunk couple began seeing evil spirits in the children before strangling the boy with an electric cord and stabbing the girl to death.

After the attack, Muradyan called for help from a neighbour’s son, a doctor.

The medic said: “The boy was already dead and the girl was wheezing.”

He called an ambulance and the police, but the girl later died in hospital.

The grandmother was ruled to be “sane” and was sentenced by a Russian court to 16 years in jail.

The judge found that the grandmother’s lover simply identified as Yury was unaware of his actions during the murder due to a “temporary mental disorder” brought on by “alcoholism.”

This condition “deprived him of the ability to recognise the danger of his actions and to control them”, said a court statement.

He was sentenced to compulsory psychiatric treatment.

The children’s “distraught” parents Natalia and Alexander split up after the murder of their son and daughter in January last year, said reports.