LONDON.- Four months after the British Museum fired a curator suspected of stealing gems, jewelry and semiprecious stones, the London institution on Tuesday released further information about the fate of the missing items.

Officials assume that around 1,500 artifacts were stolen or are otherwise missing from its Greek and Roman stores, the museum said in a news release. Another 350 items have been damaged, the statement added, including by gold having been removed. Those gold parts were “likely to be unrecoverable,” the museum said, and were probably sold to scrap metal merchants.

Another 140 items that remain in the museum’s possession “have been damaged by tool marks,” the news release added.

Of the missing 1,500 items, just over 350 had been returned, a British Museum spokesperson said in an interview. Another 300 items had been identified but not recovered.

The spokesperson said that all the returned items had come from Ittai Gradel, a rare gem dealer who, in 2021, first alerted the British Museum to the losses, only to have his concerns rebuffed. Previously, Gradel had bought some of the items before realizing they belonged to the museum.

The spokesperson said that the museum estimates the thief only made around 100,000 pounds ($125,000) selling the artifacts via websites including eBay, based on the items’ listings. Further details of the missing items could not be released because of an ongoing police investigation, she added.

The British Museum has given regular updates on its investigation since it announced the thefts in August. In October, George Osborne, the museum’s chair, and Mark Jones, the museum’s interim director, unveiled a $12 million, five-year project to improve the British Museum’s record keeping.

On Tuesday, the museum also released some details of an independent review into the thefts, by Mark Boardman, a senior lawyer; Ian Karet, a British judge; and Lucy D’Orsi, a police official.

The review’s main recommendations for how the museum can improve its security were not made public, but the British Museum published 36 other suggestions on its website. Those cover improvements to the museum’s policies and management procedures, including more frequent inventory checks.

Osborne, who declined an interview request, said in the news release that he had accepted all the review’s recommendations. The British Museum was “putting our own house in order,” he added.

This article originally appeared in The New York Times.