The Campania region, which includes Naples, has announced that it will be closed on Friday as the number of Covid-19 cases increases.
Protesters fired tear gas and other missiles at police who responded with tear gas.
There are unconfirmed reports that protesters attacked local government offices.
Jacob Wandris posted a video caption of the disorder on Twitter: “Protests against the Big-Region government’s COVID-19 ban are now taking place in Naples, Italy.
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“The situation seems to be spiraling out of control. Thousands of people have also attacked regional government offices on the streets fighting with police.”
Footage posted on social media showed thousands of protesters, many wearing masks to protect against the coronavirus and marching across the city.
During their march, many chanted “Freedom, freedom, freedom.”
Radio Savana, which is part of the protest, tweeted: “All Naples in rebellion!
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“The population is protesting against the lockdown.
“Curfew order triggered at 11.00pm, images live: Civil disobedience continues.”
They later added: “Protests are also taking place in Salerno, Nocera and other cities in Campania.”
The number of Covid-19 cases in Italy has increased sevenfold since the beginning of October.
Campania regional president Vincenzo de Luca has ordered a night curfew and school closures.
He posted on Facebook: “Current data on infection invalidates any kind of partial measurement. Everything needs to be shut down except for businesses that produce and transport essential products.
“It simply came to our notice then. We need to shut everything down for a month, for 40 days. “
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