(CBS News) The blue and gold braided beard on the burial mask of famed pharaoh Tutankhamun was hastily glued back on with epoxy, damaging the relic after it was knocked off during cleaning, conservators at the Egyptian Museum in Cairo said Wednesday.

The museum is one of the city’s main tourist sites, but in some areas, ancient wooden sarcophagi lay unprotected from the public, while pharaonic burial shrouds, mounted on walls, crumble from behind open panels of glass. Tutankhamun’s mask, over 3,300 years old, and other contents of his tomb are its top exhibits.

Three of the museum’s conservators reached by telephone gave differing accounts of when the incident occurred last year, and whether the beard was knocked off by accident while the mask’s case was being cleaned, or was removed because it was loose.

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