Suspicions were raised when experts realised the insects originated in Central and South America and some were "disorientated".
Nurses at a hospital in Naples may have released cockroaches into a ward in order to get it closed, police have said.
United Kingdom: Media in the southern Italian city have reported detectives suspect the insects were introduced to the Accident and Emergency ward at the Vecchio Pellegrini Hospital by staff who wanted to be transferred to less demanding jobs.
A patient filmed some of the bugs and put the video on social media.
Hospital director Maria Corvino told The Times it was "extraordinarily grave".
"Nurses and trade unionists appear to have sabotaged the Pellegrini in order to obtain a transfer elsewhere," she said.
It is believed the bugs were brought into the hospital in a bag containing sawdust and a sheet.
Authorities' suspicions were raised when an expert found the cockroaches were not local ones, but from Central and South America.
Emilio Noviello, from the University of Naples Department of Veterinary Medicine, told a local radio station they were "examples of Blaptica dubia, which come from Argentina and Brazil."
That accounted for the fact that some of the insects appeared to be disorientated when they were found, while others were on their backs as if they had just been scattered, he explained.
Such creatures are "normally used to feed reptiles" and readily available "both on the internet and in specialist shops dealing in exotic animals," he added.
It is not the first time staff have been suspected of introducing insects to hospitals in the city.
Last year, a patient at the San Giovanni Bosco Hospital was filmed covered in ants.
An investigation found open sachets of sugar scattered around staff lockers.
Last month, a further infestation of ants was found in the resuscitation department.
News Courtesy: Sky News
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