A riot police officer shoots a tear gas cannister during a protest in Santiago, Chile on Monday. Chile ordered an overnight curfew for the third day in a row on Monday as violent demons-trations and looting continued for a fourth straight day. Photo: AFP

Chilean President Sebastian Pinera announced a package of social measures Tuesday aimed at stemming days of ­protests over economic inequality that have swept the country and claimed 15 lives.

Apologizing to the nation for failing to anticipate the outbreak of social ­unrest, Pinera said his government had "received with humility and clarity the message Chileans have given us."

The leader vowed to increase the universal basic pension by 20 percent, cancel a recent 9.2 percent increase in electricity bills and propose a law that would see the state cover the costs of expensive medical treatment.

"I recognize this lack of vision and I apologize to my compatriots," Pinera said in an address from the presidential palace in Santiago.

Pinera also pledged a state subsidy to increase minimum wage to 350,000 pesos ($482) a month and said the government would introduce health insurance for medication, which is among the most expensive in the region.

Earlier in the day he met with the leaders of some of Chile's opposition parties as he sought a way to stem 

the country's worst violence in decades, initially triggered by an increase in ­metro fares. 

The protests, which began Friday, mushroomed into a broader outcry against social and economic woes, including a yawning gap between rich and poor, in a country normally considered one of the most stable in Latin America.

Pinera quickly suspended the metro fare hike, but also declared that Chile was "at war against a powerful, implacable enemy," and imposed a state of emergency in Santiago and most of Chile's 16 regions.

Adopting a more conciliatory tone, he later called for Tuesday's meeting, which was boycotted by three of the largest opposition groups, including the powerful Socialist Party.

The day's protests were mostly peaceful, particularly in the capital, although looting continued in other towns.

But with the country's largest union, the Workers' United Center of Chile (CUT) alongside 18 other social organizations, calling strikes and protests for Thursday and Friday, the pressure had been on Pinera to act.

On Tuesday the army announced a nighttime curfew - from 8:00 pm to 5:00 am - for the fourth day in a row.