The 88-pound plaques were stolen from a memorial dedicated to the Royal Navy and Royal Marines in Plymouth, England, The Times of London reported Wednesday.
Officials said the items may have been stolen to be sold as scrap metal.
"One can only imagine the pain this is causing to the relatives of the men in Plymouth," said Peter Francis of the War Graves Commission.
The newspaper said it will probably cost at least $16,000 to replace the plaques, which are only valued at about $400 each as scrap.
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