A 26-year-old man has admitted murdering his 84-year-old grandmother and attempting to murder a nine-year-old boy.

Nathaniel Flynn pleaded guilty to killing Louisa Denby at their home in Shipley, in July and stabbing the boy in a nearby skate park.

Flynn, of Prospect Mount, Shipley, was due to go on trial next week but pleaded guilty to the charges at a hearing at Bradford Crown Court this afternoon.

He will be sentenced on December 18.

After the hearing, Detective Chief Inspector Nick Wallen of West Yorkshire Police said: "Louisa Denby was subjected to a brutal and frenzied attack at the hands of her grandson Nathaniel Flynn.

"To this day we still have no idea why he attacked her. Louisa was a lady, adored by her family, who had only ever shown her grandson love and kindness.

"Having murdered his grandmother, Flynn then targeted and attacked nine-year-old Jason D'Arcy as he played in a skateboard park not far from his home.

"Jason was stabbed through the arm and it was only through sheer luck that he wasn't murdered by Nathaniel Flynn on that day."

Mr Wallen said Flynn then tried to entice an eight-year-old girl from her garden where she was playing and later assaulted a 59-year-old man outside his home.

The detective said: "On behalf of West Yorkshire Police, I would like to pay tribute to the people of Shipley who assisted the police to quickly detain and arrest Nathaniel Flynn.

"I would also like to thank all of those members of the local community who provided the police with witness statements.

"It is because of your evidence that Nathaniel Flynn has pleaded guilty to his crimes today."