Egyptian prosecutors have referred eight museum staff for trial after a botched attempt to glue King Tutankhamun's beard back on to the ancient burial mask, according to local media reports.

The staff face charges of negligence and violating professional standards after the 3,000 year old artefact was damaged.

Staff gave differing accounts of how the beard became detached including claims it had been knocked off during cleaning. Others said it had been removed after coming loose.

Prosecutors say the employees improperly handled the piece on two occasions in August and November 2014 causing the chin on the mask to detach and then worsened the situation by using the wrong glue to reattach it.

They said these actions were “flagrant violations to scientific and professional standards", which “caused damages and scratches” to the piece.

The mask pictured during during restoration in Cairo in October 2015 Credit: Reuters

The referred workers include the former general manager of the museum, the former head of renovations and six other antiquity maintenance staff.

A German restoration team was summoned to restore the piece and it was back on display in December 2015.

The mask is a star attraction at the Museum of Egyptian Antiquities in Cairo.