If you've walked the streets of Paris or any other major French city in the last few months, you'll no doubt have noticed the soldiers and police officers - often standing in pairs - guarding "sensitive" sites like Jewish schools, media outlets, and Muslim places of worship.
They've been there since the terror attacks on the Charlie Hebdo offices and a Jewish supermarket in early January, when 17 people were killed in what are known as the Paris terror attacks.
There have been no terror attacks since, and burglary levels have dropped in the capital, but the officers with the CRS, who are charged with controlling riots and protecting public buildings, are reportedly getting tired of being on guard all day.
As they are prevented by law from going on strike they're making their voices heard by calling in sick, according to various reports in the French press.
The "sick protest" began on Friday in Toulouse, southern France, when officers from the CRS first said they were too sick to work.
They were followed by CRS officers in northern Nancy and central Lyon on Tuesday.
(Ile-de-France and Alpes-Maritimes will remain on high alert for months. Photo: AFP)
They're "fed up" with a "very tense working environment", Nicolas Comte, head of one of the police units, told France Info.
One police spokesman has already spoken out about the risks of the long shifts, saying in March that overworking could lead to complacency.
"The risk is that this will lead to a lack of vigilance, which means that when a real attack comes we are not reactive and therefore unable to stop it," he told Europe 1.
There are around 1,000 CRS guards on hand across the country, together with 10,500 soldiers, who form part of the country's national terror alert system, known as Plan Vigipirate. They are guarding over 800 sensitive sites.
The government announced in March that the system would remain at "attack level" until at least April 10th in Ile-de-France and in the Alpes-Maritimes region around the Riviera, though reports suggest it will stay in place "for months". The rest of France would remain at "high vigilance" level.