Coca growers clashed with police in the Bolivian capital, La Paz, on Monday, the latest in a series of violent confrontations that have lasted for nearly a fortnight.
The police dispersed the farmers by firing tear gas grenades after the demonstrators threw firecrackers highly explosive.
Several coca growers' unions have been fighting for months over the leadership of the La Paz farmers' association, effectively seeking permits to sell coca leaves on the local market.
The conflict turned violent in September, when one of the different groups fighting for leadership took over a building that houses their association.
There are an estimated 100,000 legal coca farms in Bolivia, and the buying and selling of coca leaves is a legal business in designated markets run by the coca unions.