Taylar Isaac, 20 of Amhurst Road, Hackney and David Kerrigan, 20 of Brackenfield Close, Hackney were found guilty of murdering 29-year-old Joshua after a trial at the Old Bailey that concluded on Friday, 16 April.
Theo Momodu, 18 of Overbury Street, Hackney had previously pleaded guilty to murder.
All three men were also found guilty after trial of Section 18 GBH (wounding with intent) in relation to an attack on another man.
Harley McGivern, 20 of the Beecholme Estate, Hackney was found guilty of perverting the course of justice.
Sentencing will take place at the same court on a date to be determined.
The court heard how a text message sent to Momodu from a person believed to be in prison urged him and other members of his gang to ‘ride out’ and attack people as a demonstration of loyalty.
On the afternoon of Friday, 26 April, Momodu, Isaac and Kerrigan carried out that instruction with devastating consequences.
They were driven by an unidentified man in a stolen white SUV to Brenthouse Road, E9 where, armed with knives and swords and wearing balaclavas, they confronted the occupants of a grey Mercedes.
The Mercedes made off and was pursued by the gang.
Seconds later, CCTV captured the three men chasing Joshua White on foot, still brandishing their weapons.
Joshua ran towards a shop in Frampton Park Road, colliding with a six-year-old girl on roller skates who was innocently waiting outside. The girl and Joshua went crashing to the floor.
He briefly paused to check she was ok before getting to his feet. But as he reached the door of the shop he was caught by Momodu and Isaac and stabbed multiple times. Kerrigan was also seen on CCTV, stood yards away.
Joshua collapsed inside the shop and despite the efforts of the emergency services who rushed to the scene, he died in hospital later that day.
Not satisfied with stabbing just one person, Momodu, Isaac and Kerrigan returned to their white SUV and made off.
In nearby Wilton Way, they found a man they recognised from a local estate. He was with his partner and young child but the gang set upon him anyway, stabbing him multiple times as he attempted to flee. Fortunately, he survived his injuries.
As the attackers drove away from the scene, the registration of their white SUV was being circulated to nearby police units. Armed officers in an unmarked vehicle spotted them and gave chase.
The driver of the SUV crashed after a short pursuit and the occupants ran in different directions, shedding layers of clothing in an effort to disguise their identity.
Momodu was arrested nearby. The other men were identified and arrested some time later.
Detailed analysis of CCTV in the hours before and after the attacks established that McGivern had allowed his flat to be used as a base for the gang and that he had personally helped to dispose of clothing and other evidence. He was arrested and charged for his role.
Detective Sergeant Andy Sheppard, from the Met’s Specialist Crime Command, said: “These three men went out that day with the clear intention to stab people. They didn’t care who, as long as it earned them respect and notoriety in their gang.
“Joshua appears to have been targeted at random. He was chased in broad daylight and savagely stabbed just yards from an innocent six-year-old girl.
“Unbelievably, they went on to target a second victim, also in front of a child, and again for no apparent reason.
“There is no place for this sort of mindless brutality on the streets of London. Young men caught up in this way of life may think they are proving themselves and building a reputation, but in reality they are just cutting short their own lives and the lives of others.
“The community is safer knowing that they will be behind bars for a long time.”
Joshua’s parents both released statements following the verdict.
His mother, Trisha Sargusingh, said: “My son Josh was a kind, loving, happy and caring son. A loyal friend and a sensitive and humble man.
“His passing has left a hole in my heart that will never be filled. From the time of his senseless murder we, as a family, have been mourning not only for him but for the loss of all the experiences, hopes and dreams that he will never now fulfil.
“Coming to court has been so difficult, physically, emotionally and spiritually and although there is no punishment severe enough that can alleviate the horrific manner of Joshua’s death we are hopeful that a strong sentence for those convicted may be a deterrent so that other families may never know a pain like ours.”
Joshua’s father, Leigh White, said: “Upon receiving the verdict today, I would like to say thank you to everyone involved who has contributed to achieving this outcome. The past two years have been extremely difficult not only for myself, but for all of the family and close friends whom Joshua left behind.
“The conviction of those who took his life will not bring Joshua back or ease our pain, but we hope that it will bring us a measure of comfort from which we can start to heal.
“ I hope that today’s verdict will have lasting consequences for those who committed such a heartless and shameful killing and stands as a lesson to others who are considering carrying knives which could result in the loss of other innocent lives.
“Joshua’s life was cut short in such a meaningless and senseless killing. I hope that those responsible recognise the deep psychological and emotional damage that this has inflicted on everyone who knew him.
“Joshua was a caring, loving, beautiful, kind-hearted person, and his death has left such a huge void in all our lives. Life without him will never be the same again. Whilst our pain will never heal, we hope that in time it will become easier for us to bear.”