A CRACK addict who fractured the skull of a boy suffering from Asperger's Syndrome in a vicious attack in Rayners Lane was jailed for six years last week.

Harrow Crown Court found Leon Thompson, 20, of no fixed address, guilty of GBH with intent against Jonathon Davies in the attack in Alexandra Avenue in August 2004.

Thompson, originally from Perivale, launched the assault on Mr Davies and his friends as they left Rayners Lane station at 7.30 in the evening. Together with another man, who has never been traced, he knocked Mr Davies to the ground and "kicked his head like a football" while his friends were powerless to intervene. Although the attack was thought to have been an attempted robbery, nothing was stolen and the judge said she therefore treated the attack as "motiveless."

Mr Davies, then aged 16, suffered a fractured skull and bruising to the brain, which left him with impaired speech and movement on one side of his body. Although he made a full recovery from his physical injuries, the attack was said to have "set him back two years" in his progress from his medical condition, which is similar to autism.

On the day of the attack Thompson, who had a previous conviction for robbery, had also stolen a car. He had turned to crime to finance his drug habit, the court heard. His lawyer said that, since he had been free of drugs, Thompson had appeared to be a reformed character and that his girlfriend was now pregnant with twins.

Mark Cotter, defending, said:"It is only crack cocaine that can explain why the intelligent, courteous young man who I have been dealing with should have behaved in this way. The victim's injuries are a tragedy, but it also a tragedy that a young man who is otherwise morally upright should have been driven to these acts. There is absolutely no doubt that crack cocaine is a savage drug that can have a pernicious effect on individuals."

Immediately after the assault, Thompson ran after one of Mr Davies' friends and cornered him in an alleyway, warning him "you didn't see nothing."

Sentencing Thompson to six years, Judge Susan Tapping said: "You kicked the accused repeatedly in the head until he was unconscious, and then left him for dead. Not only was this a gratuitous and sustained attack, but you were sufficiently aware of what you had done that you chased and intimidated the main witness, threatening him to keep quiet. It is not difficult to conclude from these facts that you represent a significant danger to the public."

Thompson was caught after he returned to Rayners Lane station and footage was seen on CCTV. Police said that Thompson's distinctive physique (he is six feet five tall) enabled his identification by the victim.

DS Richard Tobias, who led the investigation, said: "CCTV was certainly key in this case in identifying someone of a distinct appearance. This was a suitable sentence and hopefully should allow the victim to feel that the chapter in his life is closed."