A teenage pupil at a Berkshire girls school has died in "unknown" circumstances after a short illness.
The 15-year-old pupil, of The Holt School in Wokingham, died on Wednesday in hospital.
A letter was sent to parents from the Health Protection Agency telling them of the death and warning them of a flu-like illness affecting schools.
The agency said it was not linking the girl's death with influenza and it did not intend to cause any confusion.
Situation 'monitored'
Philippa Nunn, headteacher of the school in Holt Lane, said counsellors had been brought into the school to support students.
She said the pupil, who has not been named, had suffered a "short illness".
In a letter to parents, Dr Muhammad Abid, a consultant in communicable diseases at the agency, said: "Sadly, a 15-year-old pupil of the school died in a local hospital earlier today (Wednesday).
"At this stage the cause of death is not known but further tests are being carried out to establish the diagnosis.
"We are monitoring the situation closely and will keep you informed accordingly."
A spokesman for the agency added they were still keeping an open mind over the death and that parents should not worry unduly.