Urfan Sharif, who was jailed last month for the murder of his 10-year-old daughter Sara Sharif, has been attacked in Belmarsh prison.
He is believed to have suffered cuts to his face and body which required stitches.
He received local care inside the prison.
A Prison Service spokesperson told Sky Information: “Police are investigating an assault on a prisoner at HMP Belmarsh on January 1.
“It would be inappropriate to comment further while they investigate.”
A Metropolitan Police spokesman said officers were investigating “an allegation that a prisoner was assaulted in Belmarsh”, adding that “the 43-year-old man suffered non-life-threatening injuries”.
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sharif and SarahThe girl’s stepmother, Beinash Batool, was sentenced to life in prison in December for years of horrific “torture” and “despicable” abuse that culminated in the murder of the 10-year-old girl.
The court heard she suffered “unimaginable pain, misery and anxiety” while she was repeatedly beaten, burned, bitten and restrained at the family home in Woking, Surrey.
Sharif was given a minimum sentence of 40 years and Batool was given 33 years.
Sara’s uncle, Faisal Malik, 29, found guilty of causing or allowing her death, was sentenced to 16 years in prison.
In a televised ruling on Outdated Bailey, Judge Cavanagh said Sara’s death “was the culmination of years of neglect, frequent assaults and what can only be described as torture”, mainly at the hands of Sharif.
The senior judge said his “despicable treatment” occurred “in plain sight and in front of the rest of the family.”
He told Sharif: “You treated her that way because you felt you had the right to impose harsh discipline on her.
“Sara was a brave, feisty and energetic girl. She wasn’t submissive like you wanted her to be. He confronted you.”