Thousands of striking workers, including healthcare workers and teachers, sang and carried banners in the capital and other cities.
Students and trade unionists led marches through Santiago on Wednesday in the first formally organised demonstration against social inequality since Chilean President Sebastian Pinera pledged social reforms to try to quell days of rioting.
Thousands of striking workers, including healthcare workers and teachers, sang and carried banners in the capital and other cities. The largely peaceful marches were monitored by police and soldiers.
The gatherings dovetailed four days of protests, arson attacks and looting which has seen more than 6,000 people detained and at least 15 people killed. Thousands of Chileans defied a state of emergency and military curfews.
Trade unions and social organisations wanted a voice in the rollout of a social reform plan announced by Pinera on Tuesday night, said Jose Perez Debelli, president of the National Grouping of Fiscal Employees (ANEF), one of the unions that called the strike.
"We must carry the voice of those who are on the street, to channel anger and discontent over the inequality of our country," he said.
The Copper Workers Federation (FTC), which includes unionised workers from each division of state miner Codelco, the world's top copper producer, agreed late on Tuesday to join the general, nationwide strike on Wednesday.
Codelco said one of its mines was shut and operations at a smelter drastically reduced.
Six of Codelco's eight divisions were carrying on with the "majority of their operations," the company said in a statement.
Copper producer Antofagasta Plc said on Wednesday protests in Chile could cut its production by about 5,000 tonnes, equivalent to less than 3% of third-quarter output, because of delays in supplies and travel disruptions for workers.
Jimena Blanco, Head of Latin America research at consultancy Verisk Maplecroft said it was "a matter of time" before the knock-on effects along the supply chain had a negative impact on the mining industry.
"For example, yesterday’s strike by the port workers’ union affected 20 of the country’s maritime facilities, including key mining export ones in Antofagasta and Iquique," she said.
In his announcement, Pinera said he hoped to turn the violent protests into an "opportunity" for Chile.
Pinera's proposed reforms include a guaranteed minimum wage, a hike in the state pension and the stabilisation of electricity costs.
The president said the package represented "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.
Venezuela's socialist president Nicolas Maduro on Wednesday celebrated developments in Chile, saying they represented victory in a battle "to dismantle the neoliberal model."
Pope Francis, originally from neighbouring Argentina, said he was concerned over the protests.
"I hope that by ending the violent demonstrations, through dialogue, efforts are made to find solutions to the crisis," Francis said at a general audience in St. Peter's Square on Tuesday.
There were angry scenes in the Chilean chamber of deputies on Tuesday after a group of far-left lawmakers sought to challenge Interior Minister Andres Chadwick over the numbers of people detained, injured and killed since the protests began.
Photographs and videos are circulating on social media apparently of excessive force used by police and soldiers. Reuters has been unable to confirm the authenticity of the images.
Chile's Human Rights Institute (INDH) said it received a complaint of torture in a central Santiago metro station and urged the authorities to investigate. The group said it had also registered 173 civilians injured by firearms since the weekend.
Prosecutors said on Wednesday afternoon that 6,493 people had been charged for involvement in protests and rioting since Saturday.
Joaquin Lavin, the mayor of the upmarket suburb Las Condes east of Santiago, raised concerns about the shooting of three people outside a condominium in the early hours of Tuesday morning when a military curfew was in place. One person remains in serious condition in hospital, Lavin said.
The mayor said parents who lived during Augusto Pinochet's military dictatorship from 1973 to 1990 understood military curfews better and should explain the concept to their children.
Soldiers should also exercise caution using their weapons in a heavily-populated area, Lavin said. "Those who use force must use it prudently," he said.
Justice Minister Hernan Larrain said the deaths and injuries was a source of "deep pain" for the government.
"Our commitment to democracy is inalienable and inseparable from the respect and protection of human rights and the operation of the Rule of Law," Chilean daily La Tercera quoted him as saying.