"We have all seen the images of the violence that shook Milan and other Italian cities over the weekend," Meloni said in a video statement.
The unrest began on 17 October during demonstrations over living costs. Groups of young people subsequently attacked shops and police officers, causing extensive damage in Milan's central shopping district.
The government has ordered another 500 soldiers to Milan until the end of 2026, with further demonstrations expected on 24 October.
New offences and penalties
Under the decree, anyone who joins a group of at least five people and engages in violence endangering public safety during a demonstration can face a prison sentence of up to five years.
The maximum fine is €20,000, with increased penalties when offenders conceal their faces or cause injuries.
Justice Minister Carlo Nordio also announced a separate offence covering the organisation of groups intended to carry out violent demonstrations, including through online platforms.
Those convicted of organising such groups could face between four and 12 years in prison, according to the Italian news agency ANSA.
Authorities can also seek prompt compensation for property damage. Parents will be financially liable when their children are responsible for destruction or looting.
The decree extends preventive detention powers to people aged 14 to 17 where authorities have evidence that they pose a danger, even without a completed criminal offence.
It also introduces a presumption that people over 14 can understand the consequences of their actions unless evidence establishes otherwise, making prosecution of minors easier.
The government said it would increase capacity in juvenile detention facilities and add judicial resources to handle cases involving young offenders.
The measures entered into force immediately but must be converted into law by parliament within 60 days.
Soldiers deployed without wider police powers
The government said 500 additional soldiers would reinforce the existing Strade Sicure, or Safe Streets, security operation in Milan.
Their responsibilities include protecting important buildings, monitoring sensitive areas and supporting the wider security presence.
ANSA reported that an earlier proposal to grant soldiers broader policing powers was withdrawn after objections from President Sergio Mattarella's office.
Police unions had also opposed the proposal, arguing that maintaining public order required specialised police training.
The deployment follows disturbances that affected Milan and other northern cities over the weekend.
Milan police estimated that approximately 2,000 young people participated in the violence on 17 October, according to the Associated Press.
Authorities said more than 100 police officers were injured over two days. Police used tear gas and water cannons as rioters looted stores and set property on fire.
ANSA reported that some businesses in Milan's fashion district remained closed after the weekend because of concerns about further damage.
Milan Mayor Giuseppe Sala warned that the government's response should not focus exclusively on punishment.
He called for attention to the underlying causes of unrest while acknowledging the need to prevent further violence.
Economic protests spread beyond Milan
The new measures follow several security laws introduced by Meloni's government since she took office in 2022.
Critics of those policies argue that tougher punishments do not adequately address the economic and social conditions contributing to public disorder.
Italian government figures cited by Reuters show that the country's prison population has increased by more than 17% over four years, equivalent to nearly 10,000 additional inmates.
The government also faces a separate wave of protests by truck drivers over diesel prices and operating costs.
Demonstrations that began in southern Italy have disrupted deliveries of food and other essential goods, with retailers warning on 21 October that shortages could worsen.
Reuters reported that delayed deliveries had left fresh produce, dairy products and meat at risk of spoiling, while some transport disruptions affected supplies to airports.
The government is preparing further support for road transport companies, including measures intended to ease fuel costs.
Meloni acknowledged the financial pressures facing households but rejected the use of economic hardship to justify violent conduct.
The next demonstrations in Milan are expected on 24 October, while the additional military deployment is scheduled to continue through 31 December 2026.
