Lewis Dale guilty of murdering grandmother Irene Dale

Irene Dale was in bed when she was stabbed to death by her grandson

A teenager has been found guilty of the murder of his grandmother and the attempted murder of his grandfather in an attack "like the film Psycho".

Irene Dale, 78, and husband Allan, 80, were stabbed in bed at their home in Summergangs Road in Hull last April.

Their grandson Lewis Dale, 17, who lived with them, admitted killing her but denied murder and attempted murder due to diminished responsibility.

He will be sentenced at Hull Crown Court later this month.

Dale had told the court he regularly used the drug mephedrone, also known as M-Cat, and could not remember attacking his grandparents.

'Hitchcock film'

The jury was told Mr and Mrs Dale had gone to bed at about 10:30 GMT on 26 April.

Later that night Dale entered the couple's bedroom and stabbed his grandfather in the chest.

Mrs Dale woke up during the attack and her grandson stabbed her several times before running from the room.

Mr Dale told the jury his grandson had behaved like the character Norman Bates from the Alfred Hitchcock film Psycho.

He told the jury: "I know it was Lewis but I can't understand it, why it happened."

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