A RECORDING of the boy who stabbed Olly Stephens showing him playing with a rainbow knife appeared on his phone the day before the 13-year-old died.

The boy was found guilty of murdering Olly alongside his co-defendant who is also 14-years-old on Monday, July 26.

The video -- which was played in court and has now been released to the media following the verdict -- was the source of controversy during the trial.

It shows the younger boy flicking the knife and demonstrates his dexterity with the blade.

READ MORE: Reaction and updates after boys found guilty of murdering Olly Stephens

According to the prosecution, the video appeared on the younger boy’s phone on January 2 -- the day before Olly Stephens died at Bugs Bottom fields.

During her evidence, Alison Morgan QC, told the boy: “You showed off how you can flick it and jab it.”

The boy disputed the video was from January 2, however, because he said it was recorded on his old phone and he had possession of the rainbow knife in 2019.

Ms Morgan alleged the boy recorded these videos in response to a discussion the boys and a girl were having about a rainbow knife Olly Stephens had.

He responded: “Those videos were not recorded on that date [January 2].”

READ MORE: Full story as teenage boys found guilty of murdering Olly Stephens

Earlier in his evidence, the younger boy claimed the knife he used to stab Olly -- a vegetable knife he had hidden in a bush opposite his house -- was thrown into the River Thames after the incident earlier this year.

Asked why he threw the knife into the river after the stabbing, he said: “because I just swung at someone.

“There's a chance I just stabbed someone and that's a serious crime.”

During a search of his house after he was arrested, police also found a knife hidden in a shoebox in the boy’s bedroom.

It measured 12cm in length and 2cm in width.

READ MORE: Police video shows key locations in area where Olly Stephens died

It was presented to the jury in court but they were told there was "no scientific evidence" linking the knife to the incident with Olly Stephens by the prosecution.

The jury also heard how the boy and his friends -- including the elder defendant -- had a ‘joint interest’ in knives and would pose for pictures holding them.

Asked why his friendship group was interested in knives, the boy said: “I couldn't tell you what the interest is but we are interested in them.”

He said the 'showing off' of their knives on social media was 'not meant to be serious or to scare people.'

READ MORE: Why we can't name teenagers who murdered Olly Stephens

Reading Crown Court previously heard that Olly was convinced to go to the park by a 14-year-old girl, where he was then “ambushed” by the two boys and stabbed to death.

The court heard both of the male attackers had “grievances” with Olly, while the girl is said to have described any violence against him as “karma” in the run-up to his death.

Jurors were told both of them had “grievances” with Olly for “snaking” them, while the girl is said to have described any violence against him as “karma” in the run-up to his death.

The younger boy, who was 13 at the time, used a knife to stab Olly while the older boy was fighting with him, the court previously heard.

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