Protesters and police clash in Bolivia's Santa Cruz

Riot police used tear gas to quell violent street protests in Bolivia's largest city on Friday, the latest disturbances in three weeks of unrest over demands that a new census be conducted.

Vendors and public transit workers set tires ablaze in streets and threw rocks at opponents of leftist President Luis Arce in the center of Santa Cruz, a key hub of the energy industry in Bolivia's tropical lowlands.

Television footage showed that a peasant federation office affiliated with the ruling party was looted and burned. Later, the headquarters of the largest local union, the Central Obrera Departamental (COD), was also looted.

Santa Cruz is a stronghold of center-right political forces that are opposed to the Arce government. They argue that the region is not adequately politically represented and receives fewer funds than it should, as calculations are based on a 2012 census.

On Friday, Arce announced that the government would be sticking to plans to hold the next census in 2024, announcing that it would be held on March 23 that year.

He also promised to redistribute the state's economic funds to all regions within six months of the new census results.

Santa Cruz plans to hold a people's assembly next Sunday to define its position in response to the president's announcement.

Earlier on Friday, opposition protesters in Santa Cruz set up barricades of burned tires and claimed they were beaten by police.

Luis Fernando Camacho, the right-wing governor of Santa Cruz province, said the protesters were "set upon by the police and by MAS," Arce's ruling Movement To Socialism party.

Interior Minister Eduardo del Castillo, however, said that the demonstration of vendors and drivers seeking an end to the opposition roadblocks "was the peaceful march of the people that was brutally attacked by radical sectors that seek confrontation".

Authorities offered no official count of arrests or injuries sustained in the violence on Friday.

The federal government said that four people have been killed and 178 injured in unrest over the past three weeks in Santa Cruz.

In his statement on public television, Arce called for "the return of calm, peace and normalcy in the department of Santa Cruz".