SANTIAGO (Reuters) - Chile’s President Sebastian Pinera announced an ambitious raft of measures on Tuesday, aiming to quell protests against his government with a guaranteed minimum wage, a hike in the state pension offering and the stabilization of electricity costs.

Pinera said he hoped to turn recent violent protests into an “opportunity” for Chile, to “make up for lost time, pick up the pace and take concrete and urgent steps” to resolve inequality that has sent tens of thousands into the streets to demand an economic overhaul and, in some cases, his removal.

The 69-year-old centre-right president asked for forgiveness for successive governments on both left and right that failed to act sooner to stem deep inequalities in Latin America´s fifth-largest economy.

“It is true that problems accumulated for many decades and that different governments were not able to recognize this situation in all its magnitude,” he said.

“I recognize and apologize for this lack of vision.”

The pledges came after a tumultuous start to the week for Pinera, who was widely criticized for saying on Monday that Chile was “at war” with violent protesters, as thousands of people held successive, peaceful demonstrations demanding an end to low wages and a high cost of living.

At least 15 people have died in protests that started over a hike in public transport costs, prompting a weekend of riots, arson attacks and looting of businesses and the declaration of a state of emergency by Pinera over a large swath of Chile.

Further protests are expected on Wednesday, along with a general strike called in solidarity with the demonstrations that will include the union of top copper miner Codelco, opening a potentially new, damaging front in the crisis for the world´s top producer of the red metal.

On Tuesday, Pinera held a roundtable for politicians of all colors to forge a new “social contract” to help Chile´s poor and middle-classes, who find themselves battling economic pressures.

In a speech delivered from La Moneda presidential palace shortly before 10 p.m., he pledged to up the minimum pension by 20% and increase the state´s contribution for the middle classes and women, fast-track a law to introduce a state critical illness cover, cut prices of medicines for the poor, and guarantee a minimum wage of $480 a month.

The state would intervene to stabilize an electricity utility hike, and rebalance disparities in municipal budgets to support poorer areas, he said.

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He recognized the potentially “enormous” cost of the new measures, and also announced a new tax bracket of 40% for those earning more than $11,000 a month, as well as looking to cut the wages of lawmakers and public officials.

Pinera´s offer represented “an enormous victory for our citizens,” said socialist Oscar Landerretche, a former chairman of state copper miner Codelco and touted presidential candidate for 2021.

“Chileans have managed to completely overhaul the government’s economic agenda,” he added.

Cristobal Bellolio, a political commentator based at Santiago’s University of Adolo Ibanez, said the pledges were “a step in the right direction” but added, “I don’t know if it’s enough.”

JUMP IN ARRESTS

On Tuesday, prosecutors confirmed the death toll in the unrest had risen to 15 people, adding that 5,400 people had been detained by the security forces - a significant and unexplained leap from the 2,600 earlier confirmed by a government spokesman.

There were further, massive marches around the country, triggering more clashes with police and soldiers. In a poor area of Santiago, protesters were pictured hijacking a city bus to ram into a department store.

In an open letter to Pinera, rights group Amnesty International said it was concerned over human rights violations and limitations imposed by the military during city-wide evening lockdowns.

“The sole fact that some groups or people have committed acts of violence in a protest does not authorize security forces to dissolve them with the use of force,” said Erika Guevara, the group’s Americas director.

The military general in charge of security in Santiago said he was aware of videos circulating on social media suggesting brutality by police or the military in tackling protesters and vandals.

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“We are investigating every one of these situations,” General Javier Iturriaga told reporters. “We’re not going to hide anything.”

Interior ministry sub-secretary Rodrigo Ubilla initially declined to identify the 15 killed since last Friday, but the national prosecutor’s office later named seven.

In a heated exchange with reporters, Ubilla said 11 people had died in arson attempts, looting and rioting in Santiago, while two people had died of gunshot wounds. Two others died in vehicle-related accidents, one outside of Santiago and one, further south, in the port city of Talcahuano.

Prosecutors said the Talcahuano death was that of a 23-year-old man run over by a military vehicle, and that a soldier had been charged with culpable homicide for the shooting of a man in northern Coquimbo.

The Chilean Institute for Human Rights said by Monday night it had registered 84 people injured by firearms.

U.N. human rights boss Michelle Bachelet, a former president of Chile, has called for independent investigations into the deaths in weekend protests.

“NEW SOCIAL CONTRACT”

Pinera announced his new social plan after a crisis summit with coalition and opposition lawmakers on Tuesday.

Almost all the key left-leaning opposition parties rejected the invitation to talks until Pinera showed proof of safeguarding the human rights of protesters and removed the armed forces from the streets.

Members of Pinera’s coalition and a handful of opposition figures who did attend the talks told reporters they had pushed for quick and sweeping reforms to quell the unrest and economic inequality.

“The president needs to listen to what the people are asking for, which is profound social change. He must listen to the people, not just political parties,” said former foreign minister Heraldo Munoz, head of the center-left Democratic Party (PPD).

Some politicians and protesters pointed to a leaked audio recording of first lady Cecilia Morel as proof of a disconnect between ordinary voters and Pinera, a billionaire businessman who introduced credit cards to Chile in the 1980s.

“We’ve been overrun, it’s like an alien invasion,” Morel said in the audio, which authorities confirmed as authentic. “We’re going to have to cut back on our privileges and share with the rest of them.”