A teacher has gone on trial accused of sex assaults on five boys while working at a school in Kirklees.

Ian Howard, prosecuting, told Leeds Crown Court in most of the offences it is alleged Brendan John O’Brien touched the youngsters’ genital area over their clothing.

However, in one case it is claimed he put a boy’s hand on his own penis over his clothing and told him to squeeze it, he told the jury.

O’Brien, 45, of Barnsley Road, Barnsley, denies 17 charges of sexual assault and one of causing or inciting a child to engage in sexual activity.

Mr Howard said the alleged offences came to light after one boy made a complaint after a falling out with O’Brien in January last year.

He was spoken to by his father and for the first time told him O’Brien had touched him. That led to a complaint the next day and the police being involved.

The boy said in his first term with O’Brien they were in the classroom when the teacher asked him “hands up or hands down” referring to where he should put his hands.

O’Brien having then put his hands below the table grabbed or squeezed the boys crotch area over his trousers. The boy said at that time he told no-one but felt sad because it wasn’t very nice.

That had happened again in the following weeks but not the following term which was when the falling out had happened.

Mr Howard told the jury on the night the boy spoke of what had happened to his father, his mother was talking to a friend on Facebook and mentioned what had been said.

That friend had another friend with a son who had previously been taught by O’Brien and when she heard of the allegations asked her son about “paedophile teachers” and that got him thinking about the past.

He then told her when he was at the school he too had been touched. He said he would be called back after class so O’Brien could speak to him. He would praise him and make him feel special.

When he was touched over his trousers he said he did not feel in a position to tell O’Brien to stop. He said on one occasion O’Brien had put his hands under his trousers and touched him over his underpants.

Mr Howard told the jury that boy was taught by O’Brien “in a quite separate academic year.”

The third complainant was seen by police investigating the allegations because it was became known he had called O’Brien in school a “dirty old man”. He also said he was rubbed over his clothes and “it felt weird.”

The fourth complainant said on one occasion he was taken out of another teacher’s lesson and was in O’Brien’s room when the teacher took his hand and put it over his trousers.

“He put my hand on his penis and said squeeze it”.

It also happened when he was in class. He remembered once doing maths and once on his computer when he was touched.

Mr Howard said the fifth boy described how the teacher would stroke him on his leg rubbing his thigh but did not touch his genital area.

He told the jury O’Brien was spoken to about the first boy’s allegations in January and specifically denied them. He said he felt shocked about what was being said.

He was then interviewed again in March about the subsequent revelations and denied any sexual misconduct with any of the boys. He said as a teacher he would touch the pupils as part of his job but denied there was anything sexual in that.

The trial continues.