Puno: Demonstrators protesting a proposed silver mine set fire to a customs building on Friday after a night of violence in which three government offices were looted less than 10 days before presidential elections.
A column of black smoke billowing from the customs building was visible from all points of this city of 120,000 on Lake Titicaca, some 1,300km south-east of Lima.
The violence came as Peru was in the final stretch of campaigning for a June 5 presidential election pitting a leftist populist Ollanta Humala and Ms Keiko Fujimori, the daughter of former president Alberto Fujimori, imprisoned for crimes against humanity.
Looters ransacked the town hall, a finance office and the customs building on Thursday night as the protests turned violent. On Friday, they returned to the customs building and set fire to it, police said.
Protest leaders blamed the violence on criminals who infiltrated their demonstrations. Those responsible for looting the customs house had `nothing to do with the strike,` said Walter Aduviri, one of the leaders of the group protesting a silver mine project by Bear Creek Company.
The protesters, mostly Aymara Indians, are angry that the central government granted the Canada-based company a concession to open a silver mine in the community of Santa Ana, fearing it would pollute the water and leave few local benefits.