A mother has paid tribute to her "extraordinary" 16-year-old son who was stabbed to death.
The teenager, who has been named locally as Ashraf Habimana, died in hospital after suffering multiple stab wounds during an attack in Nunnery Lane on Friday.
Three teenage boys have been arrested on suspicion of murder and remain in police custody.
Ashraf's mother described her son as "loving, caring, calm and extraordinary" on a fundraising page she set up in his memory.
Writing on the Gofundme site, Fiona Namusoke wrote: "Ashraf is my second son, my best friend, my hope, my dream, my future and the assistant carer to his extremely autistic brother.
She added: "He was a friend to so many, a confidant, an avid basketball player and a music lover with a dream to become a cyber security analyst.
"As a family, no words can explain the pain we are going through."
Ashraf's grandmother Hajat Nasim Nanyanzi visited the scene on Monday, greeting other mourners who had come to lay flowers.
Speaking to ITV News Anglia, she said: "He was growing up and he was helping out a lot in the family. We are very sad, we are not okay at all.
"He was giving us happiness at home and had a lot of friends at school."
A second teenager was injured in the attack and is being treated at hospital for potentially life-threatening injuries.
A third victim also received serious injuries, though these are not being treated as life-threatening.
It comes after violence earlier the same day when two other teenagers were stabbed in Sundon Park Road area of Luton at around 4pm.
One teenager received life-threatening injuries, and a second received serious but not life-threatening injuries. Both are being treated in hospital.
Both incidents are being connected by officers at the Bedfordshire, Cambridgeshire and Hertfordshire major crime unit.
Det Insp Lee Martin said: “Appalling violence in Luton cost a teenage boy his life, and left two others in life-threatening conditions.
“Incidents such as these have a significant impact on our residents. Our thoughts are first and foremost with the loved ones of the boy who lost his life in such tragic and awful circumstances."
Anyone with information is asked to contact Bedfordshire Police on 101 or Crimestoppers anonymously on 0800 555 111 or via crimestoppers-uk.org.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know...