SANTIAGO (AP) ― Protesters supporting a 48-hour strike called by student groups, unions and opposition politicians threw up burning barricades and clashed with police Wednesday to demand fundamental changes in Chile.

The government said 36 people ― 19 police officers and 17 civilians ― were injured and 348 people detained over the course of the day. Earlier, police Maj. Christian Kuntzman said one injured officer was shot in the hand.

The day began with a long and noisy pot-banging protest known as a “caceroleo,” conducted by students who have been boycotting classes for three months to demand improvements in public education.

Treasury Secretary Felipe Larrain had said the strike would cost Chile $200 million a day in lost production, but it was unclear Wednesday how much of a shutdown the strikers achieved.

Although Santiago’s buses and the subway mostly functioned normally, most people stayed out of the capital’s normally busy city center, leaving only light street traffic. Most stores were open, but got few customers and many employees stayed home.

Other cities and provinces around Chile also were unusually quiet.

President Sebastian Pinera said at the government palace that “fortunately, as of now, the country is functioning with considerable normality.”

Arturo Martinez, president of the organized labor coalition that organized the strike, denied that.

“This country is not normal today,” Martinez said. “The authority is not capable of saying the truth.”

Martinez said union demands include changes in pensions, health care, education, taxes and a new labor code. “And we propose a new constitution,” he added.

Public transportation functioned normally in Santiago, with the exception of some suburbs where rock-throwing protesters forced drivers to abandon routes. In various areas around the capital, activists put up barricades, blocked traffic and faced off against riot police who responded with tear gas and water cannons.

Hospitals had warned anyone but the gravely ill to stay home as a precaution, but the government said only 6 percent of health care workers joined the strike.

Unions put out far different numbers. Raul de la Puente, president of the government workers union, said that “more than 80 percent are in solidarity.”

Polls say that after three months of mass student protests, most Chileans disapprove of Pinera’s government. His approval rate has fallen to 26 percent, the lowest of any elected Chilean president.

Three high school students gave up a 37-day-old hunger strike Wednesday at their parents’ request, but said they would keep up the fight for education reform.

One of them, Gloria Negrete, who was hospitalized and reported near death, said they gave up “for our health, for the precarious state that each of us were in, because our parents were suffering.”

About 40 other students in schools around Chile continued their hunger strikes to keep up pressure on the government, which has only partly responded to demands that include calls for free schooling and improvements in the quality of Chile’s education.

Pinera reached out to union and student leaders Wednesday, saying: “They always have the doors open to dialogue. The government is ready to talk directly with them.”