CCTV cameras have been installed in boys and girls toilets at a Norfolk high school.

Parents have been told the devices at Smithdon High School, in Hunstanton, will be switched on next week.

They were written to by head John Hirst on Thursday, informing them of the move, after the cameras were installed over the half-term holiday.

In his letter to parents, Mr Hirst states: "I am writing to inform you that, over the half term holiday, CCTV was installed in the student toilets.

"In summary, the reasons for installing the CCTV are as follows: To secure the health and personal safety of all students, to prevent vandalism and damage and to assist in the effective resolution of any concerns of accusations."

The letter adds a privacy impact report was carried out, which concluded installing the cameras was "the simplest and most effective action that could be taken".

It goes on: "The cameras are designed to be able to see only the entrance to the toilets and the hand basins, students' privacy is assured. Access is restricted to the head of the site for the viewing of the cameras."

Last year, a school in the Midlands was told to remove CCTV cameras from its toilets after parents said the surveillance was "creepy".

The Information Commissioner's Office warns cameras should only be installed as a last resort.

A spokesman said: "Recording images of any identifiable individuals needs to be done in line with data protection laws and particular care needs to be taken when this involves involve children."

The Department for Education says individual schools can make their own decision.

There was an outcry from parents after cameras were installed in toilets at Acle High School last year, following a spate of vandalism.

Smithdon is part of the West Norfolk Academies Trust. Its CCTV policy states: "No surveillance cameras will be placed in areas where there is an expectation of privacy (for example, in changing rooms) unless, in very exceptional circumstances, it is judged by us to be necessary to deal with very serious concerns."

Mr Hirst said: "The installation of CCTV in the student toilets is not new to schools to west Norfolk or indeed the country - it is a common policy for many schools to ensure the safeguarding of pupils.

"We have installed CCTV at Smithdon to secure the health and personal safety of all students and to prevent vandalism and damage. We also want to be able to ensure effective resolution of any concerns or accusations.

"The cameras are designed to only see the entrance of the toilets and the hand basins. We must stress that students' privacy is assured, and that access is restricted to the head of our site team for the viewing of the cameras.

"We welcome any parents to get in touch with us with their questions and concerns about the CCTV."

The West Norfolk Academies Trust said the use of CCTV systems is for the purpose of prevention, detection and investigation of criminal activity and to ensure the security of its premises.

Cameras are also used to offer surveillance in ICT rooms and safeguarding the safety of students, staff and visitors.

A spokesperson for the trust said: "Signs are displayed to notify all users that CCTV is in operation and the images filmed are held in a secure location that can only be accessed by those who are authorised to do so.

"Every camera records simultaneously and the images are stored on disc for a period of up to 10 days. After that time all images are erased apart from any which relate to an incident subject to an ongoing investigation.

"Routine checks are also made to ensure that the system is operating in accordance with the terms of this policy, and that information relating to the recordings are accurate."