On Tuesday, Dumbuya’s family paid tribute to him, saying: “We are heartbroken by the loss of our son, brother, and grandson.
“There are no words that can describe the pain we are feeling as a family.
“Umar was a loving boy and will be dearly missed by everyone who knew him.
“Umar loved spending time playing basketball, attending the gym and time with friends and family.
“We will always remember Umar for his kindness, warmth and sense of humour.
“His death has left a devastating hole in our family, and we now ask for privacy as we take time to grieve.”
Leyton Sixth Form College said in a statement that Umar’s death had been a “tragic accident”, adding he was a “valued member of our college”.
“The college is co-operating with the appropriate authorities as they carry out their inquiries into the circumstances of the accident, and we are supporting staff and students who were present when it occurred.”
An online fundraising page has been started for his family, to help to cover funeral costs.
In a tribute to a “much-loved student”, the college said: “Umar will be remembered for his kindness, warmth, and the positive impact he had on his family, friends, classmates, and everyone who had the privilege of knowing them.
“Umar’s loss has left an immeasurable void in the hearts of all who loved them.”
