Freedom of Information requests have revealed more than 1,700 artefacts are missing from publicly funded museums and art galleries in England.
The FOI requests submitted by the Press Association asked organisations that receive funding from the Department for Culture, Media and Sport for details on objects that have gone missing over the past 20 years.
The National Portrait Gallery reported 45 "not located" items - but said they were not missing or stolen.
"The bulk of the items currently not located are photographic negatives, and for the majority of those, the image has been digitally scanned and is available to the public as part of our online collections database," the gallery said.
Meanwhile, V&A noted 180 missing objects. A spokesperson said: “This does not mean these objects have been stolen or lost; it might mean, for example, that a catalogue entry has not been updated after a collection move. Items are regularly recovered as a result of this process".
Around 550 artefacts are missing from Imperial War Museum, with the institution describing them as “typically low-value, mass-produced items".
A museum spokesman said the items "date from many years or even decades ago, long before our current collections management systems were put in place".
The Natural History Museum said it had experienced “just 23 instances of lost or missing items from a collection of 80 million, limited to small things like teeth, fish and frozen animal tissue.”
A spokesperson said: “We have robust security measures in place which we regularly review. As a world-leading science centre, it's important that researchers from around the world have access to our collection to help find solutions to the planetary emergency."
Seven items were absent from the Horniman Museum, which said it has "reviewed" security in light of thefts at the British Museum "as a precautionary measure".
The theft of around 1,500 Greek and Roman objects by a British Museum employee between 1993 and 2022 emerged in August last year, causing considerable reputational damage to the organisation.
The thefts were mainly of unregistered items – gems and jewellery. The museum said that as of December 2023, 351 items have been returned, with 300 further missing items identified.