A school that took seven days to inform parents that a pupil had been found carrying a kitchen knife has been criticised for its slow response.

Parents at Mora Primary have lodged an official complaint with the Cricklewood school’s governing body after the serious incident came to light.

Teachers discovered the three-and-a-half inch blade in the rucksack of the 11-year-old after they were alerted by concerned class mates.

Police said the boy had been showing off the knife and that fellow pupils became “concerned about his actions and welfare”.

The pupil was questioned under caution by officers in the presence of teachers and his mother before he was referred to the Youth Offending Team.

Brent Council said it would not comment on individual cases but revealed that social services are carrying out an assessment of the incident and will be in contact with the parents of the boy, who has since returned to school.

Barnet Police said it was also working with social services and the school “to ensure any welfare and support is in place accordingly”.

But parents have criticised the school after receiving a letter about the incident on Wednesday, March 12 – a full seven days after the knife was found.

One parent, who wanted to remain anonymous, said: “I am very concerned about the welfare of my children at the school, especially since the boy has gone back.

“I didn’t find out about this until Thursday, March 13. The school tried to keep it quiet and it was not until the press came to the school to interview parents that they informed us.”

In the note, headteacher Nicola Denton wrote: “I would like to personally reassure parents that this rnatter is being addressed thoroughly and every step has and will continue to be taken to ensure the safety and welfare of pupils at all times.

“Parents and carers with questions or concerns of any kind ore very welcome to contact me via the main school office.”

One parent, who wanted to remain anonymous, said: “I am very concerned about the welfare of my children at the school, especially since the boy has gone back.

“I didn’t find out about this until Thursday, March 13. The school tried to keep it quiet and it was not until the press came to the school to interview parents that they informed us.”