A 13-year-old boy with no apparent underlying health conditions has died in London after testing positive for coronavirus, his family says.
Ismail Mohamed Abdulwahab died in hospital in the early hours of Monday.
He had tested positive for COVID-19 on Friday, a day after he was admitted to London's King's College Hospital, his family said.
Family friend Mark Stephenson said the boy's mother and six siblings are now awaiting the results of a post-mortem.
381 coronavirus deaths in 24 hours
Britain reported a record daily coronavirus toll of 381 on Tuesday, more than double the number of nationwide deaths posted in the previous 24 hours.
But experts warned not to read too much in the figures, citing indications that stringent measures put in place last week to cut close-contact transmission of COVID-19 were working.
"As of 5 pm on 30 March, of those hospitalised in the UK, 1,789 have sadly died," the health ministry said on its Twitter page - up from 1,408 on Monday.
Some 25,150 people have now tested positive for the virus in Britain, including Prime Minister Boris Johnson, a daily increase of 3,009.
Data published by the Office for National Statistics (ONS) for England and Wales on Tuesday revealed that the true toll could be 24 percent higher.
The government figures cover those who have been taken to hospital and tested for the virus whereas the ONS data is for deaths in the community where COVID-19 is suspected.
"The rising death toll in recent days showed the vital importance of the public continuing to stick to the social distancing guidance which has been put in place by the government," Mr Johnson said in a video-link cabinet meeting.
"The situation is going to get worse before it gets better - but it will get better," he added.
'Beyond devastated'
A spokesman for King's College Hospital NHS Foundation Trust confirmed the boy's death.
"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," he said in a statement.
"The death has been referred to the coroner and no further comment will be made."
Following the release of the latest official figures, a 19-year-old was believed to be England's youngest victim to have died in hospital with no existing medical issues.
Ismail's family said they were "beyond devastated" by his death.
"Ismail started showing symptoms and had difficulties breathing and was admitted to King's College Hospital," the family said in a statement.
"He was put on a ventilator and then put into an induced coma but sadly died yesterday morning. To our knowledge he had no underlying health conditions. We are beyond devastated."
Mr Stephenson, a college director, has set up a GoFundMe page to raise money for funeral costs.
The page says Ismail died without any family members present due to the highly infectious nature of COVID-19.
