A teenage gang member responsible for "savagely" attacking a schoolboy with a hammer was singled out for the first time by a judge today as she sentenced him to eight years in prison.

Wasif Khan, 19, was one of 13 young Asian men to be sentenced at Bristol Crown Court today for his part in severely beating Henry Webster to the brink of death, at Ridgeway School in Wroughton, Wiltshire.

Prosecuting counsel were never able to pin the use of the hammer on any of the seven defendants charged with causing grievous bodily harm - but during today's hearing Judge Carol Hagen said she was in "no doubt that the person who held the hammer was Wasif Khan".

The judge imprisoned a total of 10 of the young men, including Khan, and gave suspended sentences to three, for their involvement in the attack which she said had "tragic consequences not only for Henry Webster, but for the defendants too".

The attack in the school tennis courts last year was previously likened to a scene from a Quentin Tarantino film by prosecutor James Patrick.

Ginger-haired Henry was left fighting for his life and needed surgery after the assault which left him with three skull fractures and brain injury.

Judge Hagen said: "What I find little short of astonishing is the fact that not a single member of staff was present in the tennis courts when the bell went."

She went on: "Given the confrontation earlier that day, which was known to staff, I simply fail to understand why no member of staff was present."

She added it was "a miracle" that Henry survived the assault.

Dozens of the defendants' family and friends filled the public gallery and gasped as the lengthiest sentence was handed to Khan, who received eight years in a young offenders' institute.

Amjad Qazi, 20, and Nazrul Amin, 19, were sentenced to 12 months and 18 months respectively in a young offenders' institute, for causing grievous bodily harm (GBH).

Four other youths convicted of causing GBH were given detention and training sentences. A 16-year-old and a 15-year-old both received eight months, another 15-year-old was given 18 months and a 17-year-old 12 months.

In the second of two trials, Aqduss Rauf, 20, and Bilal Yakub, 18, Rouble Meah, 20, Mahbub Ali, 19, and Kamran Khan, 19, were found guilty of conspiracy to cause actual bodily harm (ABH).

Faran Yaseen pleaded guilty to a charge of violent disorder at the start of the second trial.

Meah, Yaseen and Rauf received two and a half years, eight months and 18 months respectively in a young offenders' institute. Ali, Yakub and Kamran Khan were each given 12 months in a young offenders' institute, suspended for two years.

Sentencing five of the defendants this morning, Judge Hagen said: "The whole incident leaves a very ugly blot on our social landscape.

"What possessed the person wielding the hammer to do what he did is beyond comprehension."

She added: "All of them (the defendants) come from decent, honourable, hard-working families. Your involvement has brought shame on your community."

The juries in both trials were told how the gang of Asian males, from Swindon, travelled to Wroughton for the fight, after Henry was involved in a minor altercation with a younger boy during the course of the school day.

The court had heard how the fight made a "sickening sight" to shocked witnesses.

Mr Patrick, prosecuting, said: "For those there, it made a sickening sight - the sort of which you would expect to see in a Quentin Tarantino film - certainly not at a school in a village in Wiltshire."

Mr Patrick told the jury in the second trial that those charged with conspiracy had orchestrated the "revenge" attack via a series of phone call conversations and text messages.

He said: "There was a plan and an agreement, a plan between pupils at school and their older friends and relatives to teach him (Henry) a lesson, to take revenge, to attack him, to hurt him, to cause him injury."

Outside court today, Detective Sergeant Mark Wilkinson paid tribute to Henry and his family and thanked his team for their hard work during the lengthy investigation.