Kaan Aslan was chased down and stabbed through the heart by thugs armed with swords in retribution for a gang attack on the brother of the man now on trial for his murder, the Old Bailey heard today.

Mr Aslan, 20, who was not part of any gang, was “in the wrong place at the wrong time” when he was knifed in the chest in Monteagle Way, Lower Clapton, just before midnight on November 13, 2017, according to prosecutor Oliver Glasgow QC.

Medics fought to save his life but he was pronounced dead at the scene 15 minutes later.

At least five men are thought to have taken part in the “planned attack” but just one – Bruno Pateco-Te, 24, of Chelmer Road, Homerton – is standing trial for murder and violent disorder.

It originated in rivalry between three Hackney gangs, the Niners, Stokey 16 and London Fields, according to the Crown.

Just a week before the attack, the defendant’s brother, said to be a member of the Niners gang – so-called after the E9 postcode – was attacked and seriously injured after driving with his girlfriend down Rectory Road, “a street more commonly associated with his rivals”.

The attack was then “glorified” in a gang rap video posted to YouTube, which included the lyrics: “Do him up in front of his baby mother. Couldn’t give a f*** about [his girlfriend’s name]”.

“Thus it was that Bruno Pateco-Te and his friends went out looking for a potential target or targets upon whom they could vent their anger,” Mr Glasgow told jurors.

“Upon seeing Kaan Aslan, the group chased down their target and butchered him. He was spotted in the street and his attackers demanded to know where he was from, and when he tried to escape he was set upon.”

One of the stab wounds in Mr Aslan’s chest was 12cm deep and left a 5cm gash in the left ventricle of his heart.

“There was little hope of survival from a wound such as that and despite the prompt attention of paramedics and doctors Kaan Aslan died in the road, only a short distance from where he lived with his family,” said Mr Glasgow.

“Perhaps the real tragedy of what happened is that Kaan Aslan was not a member of any gang and had no reason to be the focus.

“That area was the territory of the Niners’ rivals, and Pateco-Te and his friends regarded any young man in the area as a potential target that they were prepared to attack in order to send the message: ‘If you attack one of ours, we will come for you.’”

The court heard Mr Aslan was not the only focus of the group’s “blood lust” that evening. Two cyclists had been set upon a short time before, but after being chased through Laxfield Court on the Regent Estate off Pownall Road, London Fields, they managed to escape unharmed.

“Kaan Aslan was not so lucky,” said Mr Glasgow.

The Crown alleges Mr Pateco-Te can be “linked to the act of retribution”, not only because of his “obvious motive”, but through CCTV evidence linking him to the white van used to take the attackers to and from the two attack sites, signals from his mobile telephone that correspond to the van’s route, and DNA evidence on the high-vis jackets worn by two of the attackers.

Mr Pateco-Te denies murder and violent disorder.

“This defendant is likely to claim he lent his phone and moped to someone who then took part in the violence, and that he was wrongly identified because of his phone and moped being linked to that attack,” said Mr Glasgow told the jury.

“It’s up to you to consider whether there’s any truth to his claims. Is the defendant simply an innocent victim in this and wrongly identified, or was he a willing and enthusiastic participant in a plan to seek potential rivals who might have hurt his brother?”

Over the course of the trial, which is expected to last three weeks, jurors must decide whether Pateco-Te was part of the group that travelled in the van, and whether he was part of the group that killed Mr Aslan.

“It doesn’t matter who had a weapon, or what each person did, because they shared the same intention and took part in the same shared violence,” said Mr Glasgow.

“They all knew each other and understood that the purpose of chasing and attacking their rivals was to cause as much harm as possible.”

Mr Glasgow described how the attack on Pateco-Te’s brother had come about after he attended Stoke Newington Police Station as part of his bail conditions.

His girlfriend then drove him in a Ford Fiesta along Rectory Road, which is considered part of the Stokey 16 gang’s territory.

“The fact a known member of the Niners was seen on this street was bound to lead to violence, and so it did,” said Mr Glasgow.

A Vauxhall Astra rammed the Fiesta from the side, and some of its occupants tried to smash the passenger window where Mr Pateco-Te’s was sat. The driver couldn’t escape because the Fiesta was stuck behind a bus, and then it was rammed by the other car from behind.

Joao ran off along Amhurst Road, but was chased and stabbed, and taken to Homerton Hospital where he refused to provide a statement to police.

“The very nature of the attack on [Pateco Te’s brother] is so obviously gang-related that it perhaps needs no proof, when you consider the CCTV which covers in part the chase and armed attackers as they ran down the street brandishing weapons,” said Mr Glasgow. “A group of armed men setting out to attack a rival in broad daylight without caring if someone sees them.

“But proof that it was a gang attack is provided by the fact that it was subsequently glorified by the London Fields ZT gang in a music video that was uploaded to YouTube. The gang was proud of the harm they had caused, and had no qualms about boasting about it. Little wonder then that those close to [the victim] would seek to do something about what had happened.”

The trial continues.