Residents in a small town in northwestern Switzerland voted in a referendum Sunday on whether to remain part of a German-speaking canton or join a French-speaking one.
In 1978, when Switzerland - a confederation of 26 cantons with four national languages - established the new French-speaking canton of Jura, a number of districts in the area preferred to remain part of German-speaking Bern.
The town of Moutier, with a population of 7,500, was one of them. But the issue has deeply divided residents for decades.
And separatist administrations have repeatedly been elected seeking to break away from Bern, feeling Moutier would fare better as one of the major towns in Jura than be just one of many small communities in the German-speaking canton.
A previous referendum in 2017 - in which saw small majority of people voted to join Jura - was overturned because of electoral irregularities.
So security was high this time round on Sunday and the federal authorities have sent observers to ensure that the new vote is carried out correctly.
Nevertheless, public television channel RTS reported that it had seen a letter from the canton of Bern to the federal authorities claiming that a suspicious influx of new residents in Moutier had been observed in the run-up to the vote.
The new residents were “people... for whom it is difficult to understand their connections with Moutier,” RTS reported the letter as saying.
In what has become known as the “Jurassian question”, separatists have sometimes resorted to extreme measures in the past, such as occupying offices in embassies in both Paris and Brussels.
One campaigner was even killed in 1993 when a bomb he was carrying blew up.