image sourceEPAimage captionRail officials in Turin had the task of checking passengers' green passes before they travelled
Police are on alert at several Italian stations amid threats from protesters to disrupt high-speed trains on the first day of a Covid pass.
The "green pass" is now compulsory for domestic flights, ferries and long-distance or fast trains as well as schools and universities.
Increased security was reported at stations at Rome, Florence and Rimini.
Foreign Minister Luigi Di Maio has condemned a climate of hatred over the launch of the pass.
He is one of several public figures to have been targeted by anti-vaccination protesters in recent days. Journalists and medical experts have complained of being stalked while Mr Di Maio faced death threats online.
'This measure is right'
The pass, both digital and on paper, provides proof of at least one Covid-19 vaccination, recent recovery or a negative test. It is already required for entering cinemas, restaurants, gyms and swimming pools, but it is not needed on local buses.
Passengers arriving for travel on Wednesday had their passes checked by rail staff, although children under 12 are exempt. "This measure is right, indeed it should also apply to regional trains," Rome passenger Alessia Colombi told Reuters.
School staff are also required to show a pass and two teachers were turned away by the head of a Turin school, local reports said.
Despite a vocal anti-vaccination minority, Italians have broadly backed the government's vaccination campaign, with 70.1% of over-12s now fully vaccinated, broadly in line with the EU average of 70% of adults having two jabs. However, health officials fear an increase in cases of the Delta variant.
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The No Vax movement said they would block trains at 54 Italian stations and planned further action across Italy on Saturday. The interior ministry has promised zero tolerance for disrupting services, which is a criminal offence. "It's one thing to demonstrate peacefully, but causing inconvenience to others is quite another," said a senior ministry official.
image sourceEPAimage captionThe green pass is required on high-speed and long-distance train services until 31 December
Unions have also condemned the protest movement and called for protection for train passengers and staff.
Health officials and politicians have been targeted on social media and there have been street protests condemning "dictatorships".
Among those attacked was virologist Matteo Bassetti, who was confronted by a man who then followed him, shouting "we're going to make you pay". The scientist complained of being harassed since the vaccines came out in December 2020, by letter and by phone.
Former Education Minister Lucia Azzolina has been targeted on social media and journalists including Rai News reporter Antonella Alba have been attacked by anti-vaccination protesters.
Ms Alba suffered minor injuries when protesters grabbed her mobile phone. The head of Rainews24 condemned the attack, saying it was "serious that a journalist is attacked by those use 'Freedom, Freedom' as their slogan".
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