A Swiss man is being investigated over at least one death and possibly other accidents after he dumped the contents of a cat litter tray onto the busy A7 motorway.
It is believed this is because he wanted to save having to pay a green tax when he put it in the bin.
Police say that Bernard Oldenburg, 41, dumped the contents of his cat's litter tray onto the motorway every morning on his way to work in Zurich for half a year.
Police started investigating after the frequent complaints about the unpleasant obstructions on the motorway that included small stones and eventually arrested Olden-burg from Frauenfeld, northern Switzerland, who is now facing charges over breaking traffic rules and environment laws.
They are also investigating at least one accident in which a motorcyclist died in April which police may have been linked to the cat litter on the motorway.
Costs for permanently cleaning the road from the cat toilet's contents come to £4,600, officials said.