A mentally ill man accused of stabbing his mother and sister to death in their home is unfit to stand trial.
Joshua Cohen, 28, allegedly killed Louise Cohen, 66, and Hannah Cohen, 33, in Golders Green, north London, on August 11 last year.
Cohen was arrested in nearby Golders Hill Park the following day and charged with two counts of murder.
He attended the Old Bailey for a hearing before Judge Nicholas Hilliard QC.
Members of the defendant's family sat in court as the judge ruled that he was unfit to plead.
Judge Hilliard told jurors that the defendant was unfit to stand trial due to mental illness.
Their task would not be to decide on whether he was guilty of any offence but if he did the act in question - caused the unlawful death of two people, he said.
The jury was sworn in to hear the trial of issue.
Opening the case, prosecutor Sarah Whitehouse QC told jurors Joshua Cohen had been living in an annex in the garden of the family home in Golders Green Crescent.
His siblings Hannah and Nathan, 31, also lived at the address with their widowed mother.
CCTV cameras at the home captured the sequence of events in August last year, the court heard.
At about 8pm, Cohen left his garden annex and walked to the main house.
He knocked on his mother's bedroom window and she opened the door to him as his sister vacuumed the sitting room.
Cohen allegedly went into a downstairs toilet and into the kitchen followed by the two victims.
Mrs Whitehouse said: "Hannah and Louise Cohen were never seen again. In the next few minutes both of them were stabbed to death in the laundry room in the basement."
Minutes later, Cohen emerged with blood on his head and legs, carrying blood-stained clothes upstairs, jurors heard.
He changed into a red hooded top and grey tracksuit bottoms before leaving the house, the court heard.
Just before 9pm, Nathan Cohen came home and saw bloody footprints leading to the basement where he discovered his mother and sister.
A post-mortem examination revealed Louise Cohen had suffered 13 stab wounds to the head, face, neck, body and right arm and a traumatic brain injury most likely from multiple blows to the head.
The cause of death was recorded as a stab injury to the neck and blunt force trauma to the head.
Hannah Cohen died from a stab to the neck which severed the carotid artery, Mrs Whitehouse said.