The British Museum in London has fired an employee after it discovered several valuable items in its collection were missing.  

The objects include pieces of gold jewelry, gems and semi-precious stones and glass dating from the 15th century BCE to the 19th century C.E., the museum said in a statement. The pieces were not on display but kept in a storeroom for academic and research purposes. 

The individual believed to be responsible for taking the items was fired after an “independent review,” the statement said, noting that the situation is also under investigation by the Economic Crime Command of the Metropolitan Police. The museum said it plans to take legal action against the employee. 

“The trustees of the British Museum were extremely concerned when we learned earlier this year that items of the collection had been stolen,” George Osborne, chair of the British Museum, said in the statement. “We called in the police, imposed emergency measures to increase security, set up an independent review into what happened and lessons to learn, and used all the disciplinary powers available to us to deal with the individual we believe to be responsible.” 

“Our priority is now threefold,” Osborne continued. “First, to recover the stolen items; second, to find out what, if anything, could have been done to stop this; and third, to do whatever it takes, with investment in security and collection records, to make sure this doesn’t happen again.”  

“This is a highly unusual incident. I know I speak for all colleagues when I say that we take the safeguarding of all the items in our care extremely seriously,” added British Museum director Hartwig Fischer. “The Museum apologizes for what has happened, but we have now brought an end to this—and we are determined to put things right.”  

Fischer explained that the museum has tightened security arrangements and is working with outside experts to “complete a definitive account of what is missing, damaged and stolen.”  

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

A spokesperson for the British Museum declined to comment when asked about the value of the items and when they were found to be missing, citing the “fact that this is an ongoing police investigation.” 

An investigation into the incident will be led by Lucy D’Orsi, Chief Constable of the British Transport Police, and former British Museum trustee Sir Nigel Boardman, who will jointly recommend security adjustments. “They will also kickstart—and support—a vigorous program to recover the missing items,” per the institution’s statement. 

“The British Museum has been the victim of theft and we are absolutely determined to use our review in order to get to the bottom of what happened, and ensure lessons are learned,” said Boardman, a recently-retired corporate lawyer. “It will be a painstaking job, involving internal and external experts, but this is an absolute priority—however long it takes.”