ONE of the teenagers accused of murdering Oliver Stephens said they would ‘slap up’ the 13-year-old after developing a ‘passionate’ hatred of the youngster, a court heard.

‘Olly’ was killed after he was ‘lured’ to a knife ‘ambush’ in Emmer Green in January this year, a jury was told earlier today.

Alison Morgan QC made the claim on the first day of a trial into the 13-year-old’s death at Reading Crown Court.

Two teenage boys -- who had ‘grievances’ with Olly -- stand accused of murdering him at Bugs Bottom playing fields on January 3, 2021.

The duo, now both 14 years old, deny the charges.

READ MORE: Updates as they came in from first day of Olly Stephens murder trial

The prosecution in the trial said a third teenager, a girl who also cannot be named for legal reasons and who is not standing trial, ‘persistently’ tried to coax Olly away from his Emmer Green address on the day of the incident.

At the same time, the girl was arranging for the two boys to ‘ambush’ Olly at the playing fields using social media apps including Snapchat and Houseparty.

He was stabbed to death with a knife by the younger boy in the afternoon of the third of January 2021, the jury heard.

The girl and one of the boys have admitted to the manslaughter of Olly Stephens.

Ms Morgan said: “[Olly] was attacked and stabbed by the defendants in a park near his home.

“The defendants arranged to attack Olly Stephens with a girl. She lured Olly to the location of the attack at Bugs Bottom.

“The attack had been planned by the defendants in the days leading up to January 3. They were motivated by grievances they had with Olly.

READ MORE: Murder trial of Olly Stephens due to start

“At least one of them had a knife with them. They carried out a joint attack and used the knife to stab Olly in the chest and in the back.

“They fled the scene and would seek to dispose of incriminating messages on their phones before they were arrested by the police.

“Messages exchanged in the days before the murder indicated that both defendants intended a knife should be used in the attack.

“From this, the prosecution alleges that each defendant knew about the use of a knife and intended a knife should be used against Olly. That is precisely what happened.

“The girl agreed to set up the attack by luring Olly to a location from his home address where he would be vulnerable to being ambushed by the defendants.

“Olly was ambushed by these defendants. He was attacked while the girl stood by lending assistance by her presence.

“He was stabbed once to the front and once to the back.

“After he was stabbed, the defendants fled the scene leaving Olly in the park. They knew of the seriousness of the attack.

READ MORE: Teenagers charged with murder after 13-year-old boy dies in park

“They set about disposing of evidence that linked them to the attack and the clothes they were wearing during the attack.

“They were not acting in self-defence, they both intended to cause Olly at least serious harm.

“Their ages are not a defence to the charges just because they were 14 and 13 years old.”

Throughout the first day of the trial jurors were played recordings of voice messages and videos between the defendants and the girl.

The court was first shown a video of one of the defendants brandishing a knife with a gold blade recorded on December 21, 2020.

Another video of the two defendants running with the knife in a park late at night was played in the court minutes later.

Messages which “demonstrated hostility” towards Olly were first sent up to two weeks before he was killed, Ms Morgan said.

This came after one of the defendants accused Olly of “snaking” him, causing him to develop a “grievance” against Olly.

The defendants and the girl started to set up a meeting with Olly in the first days of 2021. By January 2, “they were all engaged in exchanging hostile exchanges and had all started to talk about setting him up and attacking him”, the court heard.

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One teenager, who has not been charged but who was involved in the planning of the meeting, said to one of the defendants they felt they felt like they were “part of a murder team”.

Alison Morgan alleged of the defendant: "He knew precisely what was going on and he knew precisely what the consequences were likely to be.

“This was not an agreement to have a fight. It was an ambush on Olly Stephens when he was not expecting it. It was a planned attack which was designed to put Olly in a vulnerable position unaware of what was about to happen to him."

Later on January 2, one of the defendants in a voice recording said Olly would get 'banged' when he saw him and that he was going to get 'slapped up'.

In another voice recording from the defendant, he says 'I hate that kid [Olly Stephens] with a passion. If I was to see him right now I would end up killing him.'

The girl involved in the attack said she 'wouldn't care' if Olly died according to a message sent to one of the defendants.

On the morning of the incident on January 3, ‘hostile messages’ between Olly Stephens and one of the defendants were exchanged.

Later that day, the girl was “persistently” trying to coax Olly away from his home address but they instead settled on meeting at Bugs Bottom field in Emmer Green.

At the same time, the girl was arranging for the two boys to ‘ambush’ Olly at the location.

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CCTV footage showed one of the defendants leaving his home on an e-scooter as he travelled towards the meeting point.

More footage showed the pair meeting up at a shop minutes before the incident.

The trial is being held in special circumstances, with counsel removing their wigs and gowns due to the defendants’ ages.

The younger boy also denies two counts of perverting the course of justice.

The older boy denies one charge of the same offence, and has pleaded guilty to another.

The trial continues.