A Russian pensioner who is being investigated by police over 13 murders may have cannibalised her victims, police have said.

Tamara Samsonova, 68, was arrested in July on suspicion of killing a 79-year-old woman, cutting up her body and disposing of it in a pond. CCTV footage reportedly showed the pensioner carrying the woman’s body in a black plastic bag as she attempted to dispose of it.

A torso with one leg and one arm was discovered near a pond three days later. Upon her arrest, police allegedly found a diary in her apartment containing accounts of several other murders which she had apparently committed.

One diary entry is alleged to say: “I killed my tenant Volodya, cut him to pieces in the bathroom with a knife and put the pieces of his body in plastic bags and threw them away in the different parts of Frunzensky district.”

Such accounts were allegedly casually interspersed with quotidian entries such as ‘slept badly’ or ‘drank coffee’.

It is reported that authorities are now also investigating whether the pensioner ate parts of her alleged victims. Sources in the Investigative Committee, Russia’s leading serious crime unit, said that internal organs, in particular lungs, were removed from the bodies of victims.

When asked if police believe she may have removed the lungs for the purposes of cannibalism, they told reporters: “It is not excluded [from lines of inquiries].”

When she appeared in court last week, she told the judge: “I am guilty and deserve a punishment.”