A secondary school has gone into lockdown following an incident.
Durrington High School in Worthing said “nobody has been harmed” and it “effectively and calmly managed the situation”.
The school has not yet confirmed what the incident was but said it is now finished.
Sussex Police are in attendance at the school.
Durrington High School was one of 11 schools in the Worthing area to write to parents about “ongoing reports of violence and antisocial behaviour”.
Co-headteachers Shaun Allison and Chris Woodcock said: “Dear parents and carers.
“There has been incident in school today, nobody has been harmed, all staff and students acted in accordance with our lockdown procedure. This resulted in us being able to effectively and calmly manage the situation.
“A further communication will follow, please do not try to contact the school or your child at this time. No children or staff have been harmed and the incident is finished.
“We thank you for supporting the school and staff in dealing effectively with this situation.”
The school previously refuted claims in January that people had jumped over its walls “in balaclavas with knives”.
At the time, it said it would have gone into “full lockdown procedures and the police would have been called” if an incident such as this had taken place.
Sussex Police confirmed at the time it was an internal matter dealt with by the school and there were “no knives or intruders”.
Afterwards co-headteacher Chris Woodcock also urged parents and pupils to be more careful about reporting “falsehoods” on social media and to go to the school directly instead with any concerns.
Sussex Police have now confirmed that a girl has been arrested.
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