A tourist took two "irreplaceable" historic Japanese artefacts from a Cambridge University education centre - after mistaking them for souvenirs.
A wooden plaque and a replica school textbook were on loan for the Kaetsu Educational and Cultural Centre's annual Japan Day from a Japanese museum, and went missing on Saturday.
A frantic search was launched for the items, which were eventually found.
The pieces were loaned to the centre from the Peace Memorial Museum in Okinawa.
According to the Cambridge News, museum director Peter Roberts-Taira said he was "very relieved" they had been found, adding: "It's the first time these items have ever been out of Japan, so the museums themselves were taking a risk.
"It was Saturday, right at the very end of the day when everyone was packing away that we realised they had gone.
"One was a wooden plaque with some Japanese on it, the other was a maths book which children had in their classrooms.
"You wouldn't know they were valuable to look at, so maybe somebody just thought they could take them."
According to the Daily Telegraph, he added: "The message went out wider to people who asked their friends, and apparently they discovered a friend of a friend had thought those things were possible to take away as souvenirs.
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