Some 90,000 foreigners, most of them French, cross the border to work in Geneva, sparking tension in an area with the highest unemployment in Switzerland - 5.3 percent in March, against a national rate of 3.2 percent.
A pamphlet distributed this month outside the Geneva University Hospitals calls for the elimination of "this border scum".
"They are everywhere... in a number that far exceeds the tolerable quota, with their arrogance, their pollution, their contempt, their insolence and their privilege," the pamphlet said.
"Total war is declared," said the tract, which was reprinted by the local Socialist Party in a newsletter expressing alarm over the document's violent nationalism. "Burn their houses, their cars. Border workers, get out."
The hospital said it planned to file charges against the pamphlet's anonymous author.
The labour union that represents employees there defended the practice of hiring cross-border workers, saying Geneva's own education system doesn't train enough nurses.
"We defend all workers, wherever they're from," union secretary Julien Dubouchet Corthay told AFP.
The hospital's 10,172 employees are 48 percent Swiss and 34 percent French, its 2011 records show.
The nursing staff is 56-percent French, but 66 percent of doctors are Swiss against just 11 percent French, and 72 percent of senior executives are Swiss.
Tensions over the large number of foreign workers at the hospital erupted into the open in February, when the director general said the hospital would begin favouring Geneva residents in promotions.
"Out of 165 medical unit managers, 110 are cross-border workers. Some employees who live in Geneva have complained," hospital chief Bernard Gruson told a local newspaper.
"So I've decided to favour a return to equilibrium. That will be my priority for every promotion. It's absolutely not about ostracism, but about my role as boss to arbitrate when people are dissatisfied."
The remarks unleashed a heated debate in Geneva, and fed the rhetoric of local political party the Geneva Citizens Movement, which regularly criticises cross-border workers.
The movement also claims French criminals come to Geneva to steal from residents.
The local Socialist Party has meanwhile called for the creation of a cross-border parliament that would bring together officials from the border districts of Geneva and Vaud with their counterparts in France.
The body would deal with the entire region's housing and employment issues, the Socialist say.
"The Geneva Socialist Party is aware of the enormous distortions in both the employment and housing markets," it said.
"That's why the party is convinced that the France-Vaud-Geneva people must work together to find solutions to their problems, especially by creating appropriate democratic institutions and true tools to fight against underpaying wages."