A school has been forced to deny rumours that a teacher showed pupils an exam paper, and gave them the answers, the day before a big end of year test.

Invicta Grammar School was ordered by the exam board to carry out an internal investigation after rumours of cheating appeared on Facebook and at least one parent complained to the board about perceived cheating by this summer's AS level media studies group.

An anonymous parent also sent a letter to KentOnline's sister paper, Kent Messenger, stating: "The year 12 media studies students, who were on study leave, got an email from their media studies teacher inviting them to a revision session that would be 'worth their while attending'.

"The following day they attended the session and went through an exam paper with specific guidelines given by their teacher as to how to answer each question.

"The next day, when the girls opened their AS exam paper, they were surprised to see it was the exact one that had been shown to them the day before."

But the school, in Huntsman Lane, has denied any wrong doing and said the complaints sent to the exam board and the KM are incorrect.

Deputy head teacher Van Bui said a clip of BBC drama series Sherlock, starring Benedict Cumberbatch and Martin Freeman, had been shown to students as part of their exam that was similar to one used during the revision session. But she stressed the exam papers were not identical.

She said: "We had a query from [exam board] OCR and I conducted an investigation into it. I spoke to students from the group who attended the revision session and they did discuss a video clip from the Sherlock television programme.

"The following day when they had their exam there was a clip from the same programme that overlapped with the previous clip by about one minute.

"The teacher had looked up the clip on YouTube and used it in the revision session. It was only this question that was similar, it was not exactly the same paper."

Ms Bui said it is not uncommon, in any subject, for a teacher to realise a popular topic has not come up on an exam paper for a number of years and to advise students to prepare themselves for a question on it.

She added: "I also looked into how we store our exam papers. All exam materials delivered to the school go in packs to a secure facility, which only our exams officer has access to.

"The media studies material was taken from a sealed pack that morning. I reported back to the exam board and they were happy with the outcome of our investigation and the girls received their exam results as normal."

OCR (Oxford Cambridge and RSA) has been approached for a comment.