Protesters clashed with riot police in Bolivia's largest city Santa Cruz on Friday following three weeks of unrest amid a general strike.

Opponents of left-wing President Luis Arce also skirmished with counterprotesters from government-aligned groups including transit workers and vendors.

Local television showed altercations involving Molotov cocktails, motorcycles, firecrackers, stones and sticks.

The Unitel broadcaster showed images of Santa Cruz farmer's union offices being looted and set on fire by opposition supporters. The union is seen as being aligned with the government.

What are the protesters' demands?

Santa Cruz is a stronghold of Bolivia's right-wing opposition. Some residents demand a new census, arguing that the region pays more in taxes than it receives in services.

If census results were to show that the region's population has increased, it would be entitled to increased funding and more seats in Bolivia's Congress.

The next census is scheduled for 2024. Bolivia's last census was in 2012.

What have officials said about the unrest?

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

The government blamed Santa Cruz provincial Governor Luis Fernando Camacho for the unrest, which began on October 22 after he and other opposition groups called the strike.

Economy Minister Marcelo Montenegro said on Friday that the strike has cost around $700 million (€675 million), having aggravated food shortages and led to further price increases.

Interior Minister Eduardo del Castillo said that the pro-government counterdemonstration in Santa Cruz was a "peaceful march of the people that was brutally attacked by funded radical sectors that are seeking conflict."

Camacho, meanwhile, said that protesters were on Friday "set upon" by police and Arce's Movement to Socialism (MAS) party.

sdi/wd (AFP, Reuters, EFE)