The Finnish state-owned railway firm VR has installed signs telling passengers to take extra precautions to prevent theft on sleeper trains.
The signs tell passengers they need to check the number of keys in sleeping compartments on overnight trains, to ensure none have gone missing and might be used by potential thieves.
If there are fewer than three, they should notify on-train staff.
"The conductor can rekey the lock on the train if necessary, so the lock does not need to be changed," said VR Operating Director Toni Rinne.
Yle has heard of cases where keys have been stolen from sleeping compartments. Thieves have then gone to the cabin when the passenger has left momentarily.
"Cases where the keys have been stolen from a cabin have unfortunately materialised on our trains over the years," said Rinne.
Thefts still do occur, however. Yle reported a year ago that Metropolitan Arseni, the bishop of Kuopio and Karelia in the Finnish Orthodox Church, had valuable icons stolen on a train.
He lost a laptop and clerical attire, including a pectoral cross, worth an estimated 1,500 euros.
So far this year, 30 thefts have been reported on VR trains, compared to 15 in all of 2023.
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