Four police officers handed out a total of 25 fines of 40 Swiss francs (€35.40) during the two-day blitz in early May, local police chief Christian Ambühl told the Grenchner Tagblatt newspaper.

“Almost everyone picked up their rubbish and paid the fine without objecting. In most cases, it was just thoughtlessness,” he said.

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After the success of the recent operation, police are now looking at more deploying rubbish patrols in future – partly to raise public awareness of the problem but also to help clean up the town's image.

Grenchen already has measures in place to clean up its streets.

As in many Swiss towns, rubbish must be disposed of in official rubbish bags or by attaching municipal tax stickers to other non-standard bags to show the relevant charge has been paid.

Some people try and get around the associated costs by dumping their garbage bags illegally.

But in the case of notorious serial offenders, authorities go through rubbish bags left on the street looking for a name or an address. Around ten to 15 times a year, they are able to identify a rubbish offender. In these cases, the fine is 100 francs.

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In what can be a game of cat and mouse, however, some people cut out addresses on envelopes before putting them in their rubbish bags.

One such offender in Grenchen was only caught after a special surveillance camera was set up by police.

An industrial centre with relatively high unemployment, Grenchen was last year the subject of a controversial documentary aired by Swiss public broadcaster SRF. 

The documentary called The Silent Majority saw the town depicted as centre of voter apathy and “the shadow side of globalization”.

Many locals felt the film was unfair and that the interviews it contained were unrepresentative.