Black-hooded protesters enraged by recent fare hikes on public transportation lit fires at several metro stations, looted shops, burned a public bus and swung metal pipes at train station turnstiles last Friday.
The move was aimed at guaranteeing "the security of residents, protecting goods and the rights of each one of our compatriots who have seen complications from the actions of true criminals", Piñera said in a speech from the government palace. Frustrations over the high cost of living in Santiago have become a political flashpoint, prompting calls for reforms to everything from the country's tax and labor codes to its pension system.
Energy company Enel Chile said vandals had set fire to its high-rise corporate headquarters in the centre of Santiago.
"In the coming days, our government will call for a dialogue.to alleviate the suffering of those affected by the increase in fares", Pinera said in the broadcast address, according to Reuters.
Demonstrators took to the streets on Friday in protest over increases in the price of metro tickets, which have risen from 800 to 830 pesos ($1.17) for peak travel times. It said its workers were evacuated and no-one was injured.
Prosecutors seek murder indictment against cop who shot woman in home
Barnes, an eight-year National Basketball Association veteran, told reporters he wanted to give back to the community. Dean shot and killed Jefferson within seconds of creeping up to the property and yelling for her to put her hands up.
The Santiago Metro, at 140 kilometers (90 miles), is the largest and most modern in South America and a source of great pride for Chileans.
After Friday's protests, metro authorities said all lines would remain closed for at least two days due to the serious destruction that made it impossible to operate the system safely.
Police who had been trying to break up the protests with tear gas withdrew from some subway stations. The subway system is likely to stay closed through at least Monday.
Earlier on Friday, after a meeting with the metro chief and interior minister, Transport Minister Gloria Hutt told reporters the fare hike would not be reversed.
Metro officials say the fare price was raised because of a devaluation of the currency, rising fuel costs and the need for maintenance.
He said the government was "perplexed and dazed" by the eruption of violence, and this "must make us think about the quality of the intelligence services".