The school and youth offending team attended by a 15-year-old boy who went on to kill his 14-year-old classmate failed to share information about his self-harming and “aggressive” behaviour, a serious case review has found, writes Maria Ahmed.

Alan Pennell, now 16, was jailed for life after stabbing Luke Walmsley as he emerged from a classroom at Birkbeck School, Lincolnshire, in March 2003.

In its review published last week, Lincolnshire area child protection committee found that Pennell had been harming himself with “sharp instruments” in the run-up to the killing but was not seen by a school nurse.

The review said: “If the self-harming had been brought to the attention of the school nurse, she could have managed the case by offering appropriate support and advice.”

It also found that a youth offending team which saw Pennell after he assaulted a pupil in 2003 was aware of his self-harming, but failed to refer him to a health worker.

The YOT was also rapped for a “regrettable” failure to liaise with the school.

Lincolnshire ACPC concluded that the incident could not have been prevented.