A married teacher and his classroom assistant have been suspended over an alleged sex film.
The pair are facing the sack after a colleague discovered the film on a school computer, according to The Sun.
It is not known if the 800 pupils had access to the computer on which it was found.
The video shows a man sitting on a chair in what looks like an office, grinning and looking at the camera while a woman performs a sex act on him.
The woman also gazes toward the camera and later lifts up her top. The newspaper reports that Tim Edwards, 46, and Angela Thornhill, 50, have been suspended while bosses investigate whether they are the couple in the film.
The probe at Addington High School in Croydon, South London, is examining whether the movie was filmed on school premises.
Mr Edwards, who earns around £47,000, is head of Information and Communications Technologies - and teaches children about the Computer Misuse Act.
Mr Edwards said at his home in nearby Warlingham: "I can't talk to you about anything. The council is investigating."
Mum-of-two Mrs Thornhill, who is separated from her husband, began as a cleaner and became a classroom assistant last September. She was not answering the door at her home.
A school spokesman said: "The school and its governors are dealing with an internal issue. It would be inappropriate to comment further."
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