Demonstrators in Chile have blocked streets and set fire to buses in a protest against a controversial privatised pension plan.
The scheme, involving funds called AFPs, was launched in 1981 during the military government of Gen Augusto Pinochet.
Protesters say some 10 million people who joined have now been left with very low retirement incomes - less than the minimum wage in many cases.
They are calling for President Michelle Bachelet to scrap the scheme.
Millions of people struggled to get to work during rush hour in the capital, Santiago, and other cities after leaders of the No More AFP movement called a nationwide strike.
Luis Mesina, a spokesman for No More AFP, which has led protests in recent months, distanced the group from the violence.
"To the people who are not going to take part [in the protests] of course we apologise because our intention is not to cause them grief," Mr Mesina told CNN Chile.
Most of the barricades had been dismantled by mid-morning, said deputy interior minister Mahmud Aleuy.
He said: "All Chileans have the right to protest what they feel are their legitimate demands, but it is not right that this causes problems for other citizens."
The Chilean pension fund system has been praised by pro-market politicians and economists across the world.
It was originally intended to pay 70% of people's final salaries.