Police responded with tear gas as some protesters were seen burning trash cans.
They were the first such demonstrations in Italy since the start of its coronavirus outbreak eight months ago.
COVID-19 cases across the country have risen seven-fold since the start of the month, jumping to 19,143 on Friday and raising fears that the pandemic is spiralling out of control.
Prime Minister Giuseppe Conte has said he wants to avoid a new national lockdown that would wreck the already fragile economy, but Italian law gives regional leaders leeway to establish their own curbs, and several regions are taking matters into their own hands.
Campania's local authorities said on Friday (October 23) that they would impose a lockdown and urged the whole country to follow suit.