Police rushed to reports that trespassers were spotted at Castle School.

At around 10.00pm last night, a number of police cars were seen racing towards Castle Street down Thornbury High Street by members of the public.

One witness claimed to see around eight police cars.

Avon and Somerset Police have since confirmed there were concerns over the school site.

In a statement they said: "We were called to reports of two or three people trespassing in the school grounds.

"A search was carried out but no-one was found."

Less than three weeks after two arson attacks on the site, residents/parents/volunteers have since set up a group to watch over the school.