Italian police are seeking eleven suspects over social media death threats made towards President Sergio Mattarella.
A number of offensive posts and messages were posted on various social networks between April 2020 and February 2021.
Authorities say they suspect an "organised network linked to the extreme right" is behind the online insults and threats.
Searches have been carried out in several Italian cities, the carabinieri said on Tuesday, including Rome, Turin, and Bologna.
The suspects are all aged between 44 and 65 years old, and at least three are believed to be members of extreme right-wing groups.
This includes a 53-year-old university professor, who authorities suspect of having close ties to "supremacist and anti-Semitic groups and militants" on the Russian social network, VKontakte.
An optician, two online journalists, an administrative employee of a Rome hospital, and a student are also among the eleven suspects.
Insults directed towards the President carry a prison sentence of between one and five years in Italy.
The searches follow an investigation launched by Rome's Public Prosecutor's Office last August after a 46-year-old man from Lecce was also accused of threatening President Mattarella on Twitter.
Mattarella, 79, was elected head of state by parliament for a seven-year term in February 2015.
Last year, authorities also launched an investigation into "serious death threats" sent to Italy's health minister Roberto Speranza over his handling of the COVID-19 pandemic.