Thirteen teenagers have been taken to hospital following reports they became unwell after eating what they believed to be sweets at a London school.
The ambulance service was called shortly before midday to La Sainte Union Catholic School in Highgate.
The youngsters were treated at the scene and taken to hospital but the Metropolitan Police said none are believed to be "seriously unwell".
The force said in a statement: " Police were called by London Ambulance Service at around 11.45am on Monday, 5 October, to reports of children feeling unwell having eaten what they believed to be sweets at a school in Highgate Road, NW5.
"As a precaution, 13 children have been taken to hospital. Their parents have been informed. Nobody is believed to be seriously unwell."
They said the full circumstances are being investigated, no arrests have been made and the school has not been evacuated.
A spokeswoman for the London Ambulance Service said: "We were called at 11.44am today to reports of an incident at La Sainte Union Catholic School, Highgate.
"We dispatched a number of resources including a clinical team leader, five ambulance crews, medics in cars and incident response officers.
"We treated thirteen teenagers at the scene and took them to hospital."
A spokesman for the school said the contents of what the students ate are being investigated.
He said: "A small number of our students have been taken to hospital today after becoming ill.
"The students became ill after eating what they believed were sweets.
"The contents of what the students ate and how they came into possession of them is being investigated by the police.
"We have made parents aware of this incident."
