Any racial tensions plaguing Ridgeway in the months before the savage hammer attack on Henry Webster seemed to stem mainly from white, and not Asian, pupils, said the school’s head teacher.

Steven Colledge, 54, took up his post in September 2006, just four months before the attack in which Henry nearly died and which left him with serious brain injuries.

Henry Webster has made a £1 million compensation claim against Ridgeway Foundation School over the 2007 attack.

Mr Colledge, 54, stepped into the witness box at the High Court in London to begin the defence case and said he was aware of some “low-level disruption” during his visits to Ridgeway before his appointment.

But, in terms of racial conflict, his “overwhelming impression” from what he was told “was that any problems that did exist were problems with white antagonism towards Asian pupils”.

The school's racial problems appeared to focus on “a minority of white pupils who had leanings towards right wing political parties such as the BNP”, he told the court in his witness statement. He added: “I can confirm that a particular group of Asian pupils had been brought to my attention because it had been noted that they tended to congregate in a group of 10 to 15”.

He told the court he had seen this, but added: “I did not perceive it as a particular problem.

“In my dealings with them they were pleasant and obedient and, in my visits to the school, I was aware of other groups of pupils congregating together – for example groups of Year 11 white males – as well as lots of groups of mixed race pupils together”.

In the four months before the January 2007 attack, staff feedback suggested that school behaviour was improving, he said, adding: “I am not saying that the school was perfect, and incidents did still occur, but the general feeling was that things were getting better. The school was a lot calmer and lessons were getting better. I cannot recall receiving any feedback of any problems regarding racial tensions”.

On the afternoon of the attack, Mr Colledge was on duty outside the school when he noticed a “gathering” of around 20 pupils near the tennis courts.

As he approached it became clear that “something had happened”, said Mr Colledge. He could hear parents “shrieking” and saw several youths running away. In terms of school security he acknowledged that Ridgeway had always been an “open” school.

And he explained: “I was aware that there was no member of staff on duty on the tennis courts or the fields at the end of the school day, but essentially that is such a large area that it would have been impractical to police it properly. Essentially, however, there was no perceived need for those areas to be patrolled by members of staff as, so far as I am aware, there was never a problem”.

Earlier , Ridgeway School’s QC criticised a witness over “absurd” suggestions that staff should have imposed a blanket ban on pupils using mobile phones. That debate came on the third day of education expert Professor Gus John’s evidence over the state of race relations at the school.

Prof John has told the High Court in London that Henry would never have been attacked had racial tensions been defused – an allegation rejected by the school. And he suggested that mobile phones were key weapons of disruption at the school – with Asian pupils using them to “summon” outside help to settle playground conflicts.

But the school’s QC, Ronald Walker said it was “absurd” to say that pupils could not carry mobile phones. The school denies all blame for the attack.

The hearing continues.