A TEENAGER accused of fatally stabbing a friend at his 18th birthday party told a court yesterday the blade went into him accidentally.

David Mitchell, 19, said he had intended to throw the knife away, but it ended up going into Paul Best's back.

Newcastle Crown Court heard how Mr Best had been celebrating his birthday at home with friends when the incident happened on February 13 last year.

The blade went 13cm into his back, passed through the lower lobe of his right lung and punctured a main artery.

Brian Forster QC, prosecuting, asked Mr Mitchell: "Why did you stab him?"

Mr Mitchell replied: "I do not know."

He said he remembered people telling him to put the knife down.

Mr Mitchell said: "I intended to throw the knife away, but that did not happen. I do not know what came over me."

Mr Mitchell later said he had hoped to slash Mr Best's arm as a warning for him to keep away following a fun fight.

Mr Best was pronounced dead on the sitting room floor of his semi-detached house in North Crescent, Easington Village, County Durham, by paramedics.

Mr Forster has told jurors they may have to consider issues of provocation and diminished responsibility as the trial progresses.

Mr Mitchell, also of North Crescent, denies murder. The trial continues.