Protests spark clashes in Bolivia

Angry protesters also took to the streets in El Alto

At least 20 people have been injured in clashes between government and opposition supporters in Bolivia's second city, Santa Cruz.

Violence broke out when pro-government supporters set up roadblocks to prevent opposition supporters from attending mass rallies.

Opposition supporters are calling for increased regional autonomy and are opposed to constitutional changes.

Supporters of the president, however, are urging national unity.

Autonomy claims

A spokesman for Bolivian President Evo Morales said the clashes came as his opponents fought indigenous Aymaras at a rail crossing some 25 miles (40km) from Santa Cruz.

But the governor of the province said that people on their way to a series of demonstrations were set upon by Mr Morales' supporters.

"People on their way to this democratic festival were ambushed, they were pelted with stones," governor Ruben Costas said.

Santa Cruz is one of four wealthy eastern lowland departments which are calling for greater independence.

President Morales hopes to redistribute up to 20 million hectares.