Following the discovery of "missing, stolen, or damaged" artifacts from the British Museum's collection, the latter announced on Wednesday that it had fired a staff member and notified the police.

According to a statement, the artifacts included gold jewelry and gems made of semi-precious stones, as well as glass that dated from the 15th century BC to the 19th century.

Director of the museum in central London, Hartwig Fischer, said, "This is a highly unusual incident." The museum is best known for having collections that include Parthenon Marbles and the Rosetta Stone.

"We take the safeguarding of all the items in our care extremely seriously," he said, adding that the museum "apologizes for what has happened but we have now brought an end to this -- and we are determined to put things right."

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The Museum announced that legal action would now be taken against the former employee and that an investigation led by the Metropolitan Police's economic crime unit in London was already underway.

The majority of the impacted items were "small pieces kept in a storeroom belonging to one of the museum's collections," according to the museum.

It noted without going into further detail that none had recently been on public display and that they were mostly retained for academic and research purposes.

Outside specialists have been brought in to help produce a "definitive account" of what has been lost, damaged, or stolen, according to Fischer, who claimed that security has been reinforced.

"This will allow us to throw our efforts into the recovery of objects," he said.

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