Demonstrators react amid tear gas during a protest against the government in Valparaiso, Chile. Reuters

Three people died in a fire inside a Santiago supermarket that was ransacked early Sunday, as violent clashes between protesters and security forces continued, said the mayor of the Chilean capital, Karla Rubilar.

"We have to report that three people have been killed in a fire in a supermarket. Two burned to death and the third was taken to hospital in poor condition but later died," Rubilar told reporters.

Chileans angry over social and economic issues clashed with security forces for a second day Saturday despite a state of emergency declared to quell the worst violence in years in one of Latin America's most stable countries.

Demonstrators protest against the government in Valparaiso, Chile, on Saturday. Rodrigo Garrido/Reuters

Authorities announced a curfew in Santiago starting at 0100 GMT Sunday, after protesters set buses on fire, burned metro stations and clashed with riot police in the city of seven million.

"Having analyzed the situation and the appalling actions that occurred today, I have made the decision to suspend freedoms and movement through a total curfew," said Army General Javier Iturriaga, who is overseeing security during the state of emergency.

AFP video showed security forces blasting a crowd with water cannon, and riot police wrestling young protesters into vans.

President Sebastian Pinera appealed to people taking to the streets, saying "there are good reasons to do so," but calling on them "to demonstrate peacefully" and saying "nobody has the right to act with brutal criminal violence."

The day had started with thousands of Chileans banging pots and pans in Santiago and other cities, reflecting broad anger over economic and social conditions, including a yawning gap between rich and poor.

But clashes later erupted in Plaza Italia, ground zero of Friday's violence, and outside the presidential palace.

Riot policemen react against demonstrators during a protest in Santiago, Chile. Ivan Alvarado/Reuters

Protesters again set buses on fire in downtown Santiago, leading to the suspension of services.

"We're sick and tired, enough already. We're tired of them screwing around with us. Politicians only do what they want to do, and turn their backs on all reality," said Javiera Alarcon, a 29-year-old sociologist protesting in front of the presidential palace, which was surrounded by police and military vehicles.

Later on Saturday, the mayors of Valparaiso region and Concepcion province also announced states of emergency.

Dozens of protesters torched a building belonging to Chile's oldest newspaper El Mercurio in Valparaiso city on Saturday evening, while elsewhere in the port city a metro station, supermarkets and other stores were burned.

Agence France-Presse