A Croesyceiliog Comprehensive School teacher was knocked out after a pupil dropped a full can of Coke on her head from four storeys up - but police were not called immediately, an MP said.

Monmouth representative David Davies said the teacher, who lives in Abergavenny, is still receiving medical attention after she was taken to the Royal Gwent Hospital on Friday morning.

Mr Davies said: “I want to know why the school did not call police right away. I’m told they were following a protocol but this teacher was knocked out cold and left in a pool of blood.”

He called for a change to Welsh Government guidance, claiming the school did not involve police due to the “Crime Beat Protocol”, regulations drawn up to stop the police from being called every time a minor incident happens in school.

A senior police officer said in an email to Mr Davies: “The incident in question has been recorded as a crime by us, however the initial direction from the school was that they would deal with the incident under the School Crime Beat Protocol (that is, that they would take primacy for the investigation and subsequent outcome within the school discipline procedure, and that the police would take no formal action).”

Mr Davies said: “The victim was visited in hospital on Friday morning by a senior member of staff and told that the police had been informed. She assumed that a police investigation would be taking place.

“This was not a minor incident. The teacher could easily have been killed or left paralysed and she is still unwell and receiving medical care. I am astonished that someone thought it would be appropriate to keep the police away and try to deal with it within the school.

"There will be a natural concern that the Crime Beat Protocol is being used cover up serious incidents in our schools.”

Mr Davies said he wants to know why the “failure to act immediately” was due to the guidelines themselves or a misinterpretation by Torfaen Local Education Authority.

"Teachers should have the right to safely go about their business without fear of receiving serious injuries and they should be able to rely on their management to back them if they are attacked,” he added.

A Gwent Police spokesman said: “Gwent Police was called to Croesyceiliog Comprehensive school at approximately 09:30 on Friday 13 February to a report of a teacher being injured by a falling object.

"An officer attended and Gwent Police is currently investigating an allegation of assault. No arrests have been made, and as the investigation is ongoing it would be inappropriate to comment further at this time.”

A Welsh Government spokesman said: “This is a matter for the school and/local authority to comment on. It would not be appropriate for us to comment on.”

Colin Crick, chairman of governors at Croesyceiliog Comprehensive, said: "The school contacted the police on Friday morning regarding the incident which took place at 8.35am and was logged by the police at 9.32am.

"The acting head spoke to the teacher on the day to provide advice and to offer our full support. As this is being dealt with by Gwent Police it would be inappropriate to comment any further at this stage."