Protesters rallied Wednesday outside the congressional building in La Paz, a day after demonstrations in the city turned violent.
Miners, peasants and leftist activists have protested for months, demanding a series of economic measures including the full nationalization of the oil and gas industries.
Bolivia's Congress recently passed a bill to increase taxes on foreign oil companies.
The measure calls for the companies to pay a 32 percent tax on their oil production, in addition to an 18 percent royalty tax they already pay. Opponents say the law is not strong enough.
In Washington, a State Department spokesman Richard Boucher said Wednesday U.S. officials are in touch with Bolivian leaders on the turmoil in the country.
Some information for this report provided by AFP and Reuters.