Toilets in Geneva have been blocked by €100,000 (£88,000) in high-denomination euro banknotes – prompting prosecutors to seek the money’s origin.
Swiss media said the first blockage occurred in the vault at UBS bank in Geneva’s financial district.
A few days later, back in May, three nearby bistros were found with 500-euro notes stuffed down the pan.
Vincent Derouand, from the Geneva prosecutor’s office, said that throwing money away is not a crime – and nor is blocking a toilet.
There was no immediate reason to think it was dirty money, he said.
Mr Derouand explained: “We are not so interested in the motive but we want to be sure of the origin of the money.”
It has reportedly cost many thousands of pounds to unblock the pipes.
Mr Derouand added that two people had agreed to compensate the restaurants, which have withdrawn an earlier complaint.
It is unclear who will get the cash – which was confiscated during the investigation – if it is found to be lawful.
Last year, the European Central Bank said it was discontinuing the 500-euro note over concerns it was being used for illicit activities including money laundering.