Angry mobs of protesters smashed train stations and set fire to buildings as violence swept through Santiago after a hike in metro fares.

Sebastián Piñera, Chile’s president, declared a state of emergency in the capital after widespread arson and clashes with police in the heart of South America's wealthiest country.

On Friday night Santiago was shrouded in smoke as the high-rise headquarters of energy company Enel was engulfed in flames and authorities battled fires at metro stops and banks across the city.

The state of emergency, established by Chile’s dictatorship-era constitution, grants the government additional powers to restrict freedom of movement and citizens’ right to assembly.

Speaking in a televised address from the presidential palace just in the early hours of Saturday, president Sebastián Piñera criticised the protesters as “delinquents”. He said: “There will be no room for violence in a country with the rule of law at its core.” The demonstrations began earlier this week when students jumped metro turnstiles en masse in a campaign against a rise in fares.