Two apparently healthy teenagers have died in London after contracting coronavirus.
Ismail Mohamed Abdulwahab, 13, and Luca Di Nicola, 19, both passed away having picked up the deadly virus.
Ismail, a schoolboy from Brixton, started showing symptoms and had trouble breathing on Thursday so was rushed to hospital, his relatives said.
They told how he tested positive for the disease the following day and was put on a ventilator then into an induced coma - but he died in the early hours of Monday at King's College Hospital.
COVID-19 is so infectious that his family could not be with him when he died.
"We are beyond devastated," a statement released through a family friend said.
"To our knowledge he had no underlying health conditions."
An appeal on a GoFundMe page set up by Madinah College to help with funeral costs said: "It is with great sadness to announce that the younger brother of one of our teachers at Madinah College has sadly passed away this morning (Monday 30 March 2020) due to being infected with COVID-19.
"Ismail was only 13 years old without any pre-existing health conditions and sadly he died without any family members close by due to the highly infectious nature of COVID-19."
The appeal, which aimed to reach £4,000, has already raised more than £24,000.
One donor wrote: "I have a 13-year-old and I can't imagine what you are going through. So so so sorry for your loss. Xxx."
Madinah College said it was "overwhelmed" with the "instant support" and tweeted "may Allah accept and love you all".
In a statement, King's College Hospital told Sky News: "Sadly, a 13-year old boy who tested positive for COVID-19 has passed away, and our thoughts and condolences are with the family at this time.
"The death has been referred to the coroner and no further comment will be made."
Mr Di Nicola, an assistant chef from Nereto in central Italy, was also called "very healthy" by his family, and the NHS confirmed he had no underlying health conditions.
He was taken by ambulance to the North Middlesex Hospital in Enfield, north London, last Tuesday - but died 30 minutes later, from apparent fulminant pneumonia.
Luca's father, Mirko, told La Repubblica that his son had contracted the virus, and that the family received an email from British medical authorities saying a post-mortem swab had confirmed that.
It is believed the coroner has not officially confirmed it.
The government's latest daily announcement said 563 people have died after catching coronavirus- taking the UK total to 2,352.
A 12-year-old girl in Belgium is the youngest known person to die in Europe after catching coronavirus.
Doctors have warned that while older people with health problems are at particular risk of COVID-19, that does not mean young people will be unaffected.
Dr Nathalie MacDermott, a clinical lecturer at King's College London, said: "It is very sad to hear of the death of a 13-year-old infected with COVID-19.
"While we know it is much less likely for children to suffer severe COVID-19 infection than older adults, this case highlights the importance of us all taking the precautions we can to reduce the spread of infection in the UK and worldwide."
Dr Jenny Harries, England's deputy chief medical officer, said young people can still be affected and "it doesn't matter what age you are - you should be staying at home and observing all the social distancing measures we have highlighted".