41 years to the day after the military coup that began Chile's long and bloody dictatorship, protesters clashed with police in the capital on Thursday in a night of fury that exposed the wounds still festering in the South American country.

Riots consumed at least seven districts in Santiago overnight on Thursday, as the anniversary of the September 11, 1973 coup by General Augusto Pinochet against leftist president Salvador Allende exposed the divisions that linger on between those who supported the right-wing regime and those who emphatically reject its legacy.

The violence began in Villa Francia, a poor district in the east of the capital, where masked and hooded protesters built barricades and lit fires, fighting running street battles with police who fired tear gas to disperse them.

The disturbances later spilled into central Santiago, where security forces clashed with protesters who set buses ablaze and set up road blocks. As gunfire broke out, a woman was killed by a stray bullet and a police officer was severely injured, according to media reports.

Just after midnight, masked men began to burn vehicles through several of Santiago's poorer neighborhoods, including Peñalolen, San Bernardo, Quilicura, and Cerro Navia, while rioters attacked a police station in San Bernado.

In Renca, a police officer was injured by a gunshot, while other members of the security forces suffered injuries in the Santiago district of Puente Alto and in the town of Melipilla, to the south-west of the capital.

On Friday morning, authorities said 179 people were detained over the course of the night, mostly for "simple disorder" but also for starting fires, carrying firearms, robbery, and drug possession.

"We are the children of those you couldn't kill," reads graffiti on a Santiago wall

Four civilians and 15 officers were injured overall, said Alejandro Olivares, chief of police for the Santiago metropolitan region.

In relation to last year, arrests last night dropped by 40 percent, Olivares told VICE News.

The anniversary of the coup, sometimes referred to as Chile's 9/11, always generates tensions and violence is common. More than 3,000 people were killed or "disappeared" as the junta sought to wipe out political opposition, and many thousands more were thrown in the regime's jails.

Chile's approach to dealing with its dark past has been fraught with controversy. Many Chileans are enraged by an amnesty law that continues to protect perpetrators of abuses under the regime, while others argue that prosecutions would only revive old agonies.

A banner reads: "Where are the disappeared?"

The country also still riven by stark social inequalities despite being one of Latin America's leading economic powerhouses.

On Thursday, the country's center-left president, Michelle Bachelet, whose father was killed by the regime and who was herself tortured, urged the congress to finally repeal the amnesty law, eight years after a motion to scrap it was introduced.

"In democracy, Chile has not lost its memory and has not forgotten its persecuted, executed and missing arrested children," she said at a ceremony at the presidential palace, La Moneda, to mark the anniversary. "Neither has (Chile) forgotten the wounds that continue causing pain."

"Forty-one years have passed and surviving witnesses, victims and victimizers and accomplices are elderly,"she said.

"Many have died keeping silent. Enough of painful hopes and unjustified silences. It's time to join forces in truth and it's fundamental for those who have relevant information to provide it," she added.

Maya Fernández, a granddaughter of Allende and currently deputy in Chile's congress, told VICE News that the student-led demonstrations that have gripped Chile in recent years are directly linked to the history of Allende's aims and the dictatorship.

"It remains relevant today, yes," Fernandez said, just steps from the Salvador Allende statue outside La Moneda. "You see it at the marches, especially the young students. The presence of Allende is strong."

"Allende lives" reads a flower arrangement; on a Chilean flag is written "Never forget, never forgive"

Prominent figures from Chile's left - leaders of the Socialist and Communist parties, and the Communist Youth - marched to the monument and held a vigil under a brilliant late winter sun. Allende's final speech from inside La Moneda was heard on loudspeakers, as his daughter Isabel Allende, the current president of the Chilean senate, greeted friends and supporters.

This year Santiago was particularly on edge in the wake of a bomb attack which injured up to 14 people in a shopping mall attached to the Escuela Militar subway. Residents have been alarmed by a series of 29 bombs planted through the city this year, thought to be the work of an anarchist group. Some of the bombs — mostly unsophisticated, homemade devices — have not detonated and no one was seriously injured until the subway blast on Monday. The seaside city of Viña del Mar was also hit by two minor blasts in a shopping mall this week, one of which injured a worker.

At the ornate metropolitan government hall across the street from La Moneda, regional mayor Claudio Orrego told VICE News that no connections could be made between the string of bombings and the anniversary disturbances.

"These are criminal groups trying to take advantage of a very sad day for Chile," Orrego said.

Bachelet also rejected such acts as she spoke on Thursday.

"In Chile there is no room, and there can be no room, for violence or fear," she said.

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