A primary school child pulled out a knife on a teacher after storming out of his classroom.
The boy, who has now been excluded, left his classroom in a temper and swiped the knife from the kitchen area in the staff room of Darell Primary School in Richmond.
The boy, who was younger than 10, had the knife in his hand when he was confronted by the female teacher.
She told him to put it down and another female member of staff took the knife.
The school did not report the incident, on April 24, to police, but they were informed three weeks later.
Laura Whateley, headteacher of Darell Primary School, said: “At no point was any child or member of staff at the school at risk of harm.
“The child involved is currently excluded from school and, together with the local authority we are working with their family to offer support moving forward.
“Darell Primary School takes safety extremely seriously and the school has a zero tolerance approach to any inappropriate behaviour. The school was praised in its most recent Ofsted inspection which stated that pupils feel extremely safe in school and behaviour is good.”
Richmond Council said it was working with the school.
A spokesman said: “Richmond Council considers the safety and wellbeing of all children in our schools of the utmost importance.”
It also said the incident was not reported to police because the child was under 10 and it was dealt with swiftly by the school and council.