An educational centre at Cambridge University nearly lost two 'irreplaceable ' artefacts after they were taken by an oblivious tourist who thought they were souvenirs . The Japanese artefacts – a wooden plaque and replica school textbook – went missing from the Kaetsu Educational and Cultural Centre last Saturday as it hosted a Japan Day celebration . The replicas were loaned to the university from a museum in Japan , marking the first time they had ever been taken out of the country . Punt boats carry tourists on the river Cam past King 's College at Cambridge University . Staff launched a search after they noticed the precious objects were missing . They eventually found the tourist who had mistaken the artefacts for souvenirs and returned them with an apology . University officials said the textbook is a replica of those used in Japanese schools during World War II . During the war residents of the island of Okinawa – a key battleground for Japanese and American forces – were forced to speak the Japanese language the rest of the country used , rather than their own dialect , for the purposes of unification . The Japanese artefacts were taken by a tourist during a Japan Day celebration at Cambridge University . As punishment , those who spoke their native tongue were forced to wear the wooden plaque around their neck . The artefacts are now being returned to the Peace Memorial Museum in Okinawa . Peter Roberts-Taira , the education centre 's director , said he was relieved when he found out that the artefacts had been recovered . He said : ‘ It 's the first time these items have ever been out of Japan , so the museums themselves were taking a risk . University officials said they located the tourist and the artefacts were returned with an apology ( file photo ) ‘ 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. ’ He added : ‘ You would n't know they were valuable to look at , so maybe somebody just though they could take them . ‘ 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 . ‘ They are irreplaceable , if they are gone , they are gone forever . It 's very , very special to have them at all . '
Artefacts were on display at World War II . Staff launched a search for the wooden plaque and replica textbook . They were loaned to the university by Okinawa's Peace Memorial Museum . Tourist returned the artefacts and offered an apology to staff .