A 13-year-old girl died at her home in Brighton on Monday.
Emergency services were called to Islingword Street in Hanover at 5.45pm.
Varndean School pupil Minnie Rose Eastman was taken to Royal Sussex County Hospital in Brighton where she was pronounced deceased.
Police said there were no suspicious circumstances and the matter had been passed to the coroner for inquiries.
William Deighan, headteacher of Varndean School, said: “Minnie Rose will be deeply missed by pupils and staff at Varndean School.
"Minnie Rose was caring and thoughtful, a gentle quiet child with plenty of friends.
"She was doing well at school and came into her own in art and drama lessons.
"We’re so very saddened by this tragedy and we’re doing all we can to support the school community.
"We send our condolences to all grieving Minnie Rose's loss and ask for respect for her family at this time.”
A multi-agency group has been established, including representatives from children's social care, education and health authorities, to consider the incident.
Four police cars, two fire engines and an ambulance were called to the scene on Monday evening.
Officers were seen removing items in sealed evidence bags from the property.
It is the second tragedy to strike Varndean School this year after the death of 12-year-old Mason Warwick in March.
Mason was found dead in his bedroom by his mother.
His parents said: “He was our amazing special angel.”
An inquest into Mason's death is due to be held in Brighton on July 17.
The school has written to parents explaining what has happened.
- For confidential support, call Samaritans on 116 123.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article