A PENSIONER has gone on trial accused of sexually abusing a five-year-old boy during an alleged child sex attack.

The claimed child victim - who cannot be named for legal reasons - told police that the incident made him feel 'very sad' and that the attack hurt him.

Answering questions about the allegation Robert Simpson told police that no sex attack had ever taken place.

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He denies one count alleging the assault of a child under 13 by penetration.

It is claimed that the 79-year-old of Robin Place, Oxford, abused his young victim on a single occasion using his fingers.

His trial got under way at Oxford Crown Court yesterday.

Outlining the case to the jury prosecutor Andrew Howarth said the incident took place in Oxford in August last year.

He told jurors that the boy claimed he was using a toilet when Simpson followed him.

It was while there, the jury was told, that the alleged sex assault took place upon the boy.

Prosecutors said that following the claimed assault it was noticed that the child appeared to be 'uncomfortable' and he didn't want to sit down.

The boy later complained that his bottom was 'really sore.'

Jurors went on to watch a recorded police interview that the child gave following the incident.

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In that interview he told officers about the alleged sexual assault.

He said that it only happened once and asked how it felt he answered: "It was hurting and it makes me feel sad."

Asked by police how he later felt about what he claimed had happened to him he replied: "Sad. Very sad."

Prosecutors also told the jury that the child was previously cross examined in a video recorded setting rather than being brought to court.

During that process, it was said by Mr Howarth, the child responded to the questioning 'in large part to say he had forgotten and therefore he was no help at all when he was being cross examined.'

It was also said that the child was later examined about a month after the incident by a consultant paediatrician.

Speaking of that medical examination Mr Howarth said that no injuries were found at all.

He added: "Sexual abuse can occur with no signs. The evidence was that it's one way or the other."

The jury was also told that Simpson was not arrested for the alleged offence but gave a voluntary police interview.

During that interview he denied any wrong-doing and said the alleged sexual offence had never taken place.

He went on to tell officers that he had long finger nails at the time and that the incident 'didn't happen.'

Simpson denies the single count and the trial - which is expected to last two days - continues.