A teenager who killed a seven-year-old girl in a park has been given a life sentence and ordered to be detained for a minimum of five years by a judge who said it was a "truly exceptional case".

Katie Rough died after she was smothered by the 16-year-old girl, who cannot be named and was 15 at the time, and then slashed with a Stanley knife in a park in York, in January.

The defendant, who admitted manslaughter due to diminished responsibility at a previous hearing, appeared by video-link at Leeds Crown Court as Katie's family looked on from the jury box.

The teenager sat with her head down, clutching a soft toy, throughout the hearing.

She was flanked on screen by a court usher and a youth team leader who confirmed the girl's name when she was asked to identify herself by the judge, Mr Justice Soole.