The security forces fired tear gas in a failed effort to dislodge schoolteachers, transportation workers, Indigenous people and other Bolivians who have taken to the streets for the past two weeks, preventing delivery of food, medicine and other goods to Bolivia’s seat of government.

News reports said some 3,500 police and soldiers took part in the operation that began in the wee hours.

At least 57 people were arrested, the government’s citizens rights ombudsman’s office said.

Center-right President Rodrigo Paz’s election win last year ended two decades of socialist rule.

He promised to end Bolivia’s worst economic crisis in four decades, marked by an acute shortage of foreign currency and fuel.

Paz scrapped two-decade-old fuel subsidies that had drained the treasury’s international dollar reserves, but so far he has failed to stabilize fuel supplies.

Now Paz is under pressure from all sides, with roads into the city blocked for the past two weeks. Prices of some food items have skyrocketed.

Besides wage increases, protesters want economic stability, an end to the privatisation of state-owned companies and the president’s resignation.

The operation Saturday was aimed at freeing up a humanitarian corridor so food, medicine and oxygen for hospitals can reach La Paz, said Jose Luis Galvez, a presidential spokesman.

He said that in recent days three people died because they could not be taken to hospitals.

The government’s highway administration department said roads were blocked in at least 22 places around the country.

On Friday the government reached an agreement with miners who were striking to obtain increased supplies of fuel and explosives to do their work and an expansion of areas in which they can operate. Paz’s office did not give details of the accord.