Italian police have warned that anti-vaccine protestors have planned to commit violence at upcoming demonstrations.

       Authorities carried out searches at the homes of eight activists across Italy on Thursday and seized a number of computers.

       Police said the group had posted on social media about potential "violent actions" they would carry out at protests against COVID-19 health passes.

       The activists were "active" members of a group on the Telegram messaging platform called "I Guerrieri" ("the Warriors"), police said.

       Raids were carried out in a number of cities, including Milan, Rome, Bergamo, Reggio Emilia, Venice, and Padua. The eight suspects are under investigation but have not been arrested or formally charged.

       "House searches and computer searches conducted by the Digos and the Milan Postal Police Department against members of the "Anti-Vaxx" group," a statement read.

       "Through a Telegram group, [they] have expressed intentions that violence will be carried out during public demonstrations."

       Police said that the activists planned to use "weapons and rudimentary explosives" at one particular protest in Rome this weekend. Some members of the group had also wanted to hold a "preparatory meeting" to obtain bladed weapons for the protest in the capital.

       One of the suspects owned a gun licence and was already known to police in the Veneto region, they added.

       "[The suspect] intended to incite the other members of the group to carry out violent actions in their respective provinces of residence," police said.

       Italy introduces Green Pass for domestic travel and protests follow Italy makes COVID 'Green Pass' mandatory for public venue access

       Italy introduced a COVID-19 health pass this summer to combat the spread of COVID-19 infections.

       Rome has said there will be a zero-tolerance policy against demonstrators who block trains or incite violence to oppose the measures.