An undated handout picture released by the Metropolitan Police Service shows Jordan Douherty, 15, who died after being stabbed in east London
London (AFP) - An out-of-control birthday party, a petty squabble, a frenzied chase and another murder on a London street.
On the evening of June 23, 15-year-old Jordan Douherty became another statistic in a knife crime crisis on Britain's streets that has reached record levels this year.
The gruesome summer evening in Romford, east London, was described in harrowing detail at a trial at the Old Bailey central criminal court of the then 16-year-old murderer.
Jurors this week found the defendant guilty of murder and two other teenagers guilty of lesser violence charges.
The court was shown footage captured on mobiles phones and splashed across social media within seconds of the stabbing.
Douherty can be seen running in broad daylight, pursued by around 50 youths as tempers flared outside an overcrowded birthday party with hundreds of rowdy teens.
The victim trips over before sustaining a barrage of punches, stamps, kicks and two knife wounds to his chest.
The dead schoolboy's mother wiped away tears as the footage showed her son staggering to his feet before being attacked once more, leaving a trail of blood in his wake.
"The heartache for the family is a sentence that lasts forever," said police officer Larry Smith.
"Jordan Douherty was stabbed to death for absolutely no reason while he lay helpless on the floor," he said.
Such attacks have become common, with over 5,500 people injured in knife crime incidents in London in the 12 months to October -- a record level -- including over 90 killings.
Even during the trial, a 10-inch (25-centimetre) blade was seized at the entrance to the court's public gallery, judge Anthony Bate revealed.
- Witnesses traumatised -
Douherty was no stranger to the violence that has taken hold of many inner city communities, particularly in London.
He was a good student but was expelled from school after joining C17, a drill rap group led by his brother Roland.
The group threatened rivals with knife attacks in their songs, and nine members were banned from parts of their neighbourhood after being linked to drug dealing and a series of violent incidents.
While gang feuds and drug wars explain many of the murders on London's street, Douherty was apparently the victim of a random attack.
Tensions rose when the birthday party for a 16-year-old girl, who knew neither the murderer nor his victim, was cut short after being gatecrashed by hundreds of youths.
Its deadly conclusion dragged her and her family through the court system and left guests traumatised, highlighting the community-wide cost of each attack.
- 'Alone and bleeding' -
The mother of a 16-year-old party-goer was waiting in a car park close to the North Romford Community Centre.
She said she was still shattered as she was forced to recall the events that unfolded before her eyes that night.
"A group of about 50 boys and girls chased him down the street," she told the court from behind a curtain to hide her from the defendant.
"He tripped twice, got up, but a second time they caught him," she recalled, adding that some youths took up positions to shout encouragement and record the action.
The woman's son said he saw Douherty "alone and bleeding" as he pulled a knife out of his own side, recalling the sound of metal as the knife dropped.
An off-duty police medic who lived nearby described how he heard a "football stadium roar" from outside his house.
He dashed to the scene, finding Douherty in a pool of blood, with his head in a woman's lap.
"He was pronounced dead at the scene," he recalled.
The convicted teenager -- who cannot be named due to age restrictions -- will be sentenced in January and could face a life term.
"Those who carry knives must understand this is not a game," said Smith.
"Young men should understand what a life sentence really is, being caged, missing out on life and being released into a world that has passed them by."