LA PAZ (REUTERS) - Six local government workers died of asphyxiation in the Bolivian city of El Alto after a group of protesters occupied and set fire to the municipal offices on Wednesday, El Alto's local government said.
Tensions are high in the country ahead of a national referendum on Sunday which will ask Bolivians if they wish to alter the constitution to allow President Evo Morales to run for a fourth term.
The municipal government of El Alto - a fast-growing satellite city of La Paz - said in a statement that six of its workers had died after the violent occupation of their offices by protesters with links to Morales' socialist party.
El Alto is governed by the opposition.
Photos on local media showed the office building in flames.
Marcelo Elio, a home office deputy minister, accused El Alto's government of throwing boiling water on the protesters and causing the tragedy.
"It is a plan orchestrated inside the local government," he said.
Rifts have deepened in recent months between supporters of Morales, who credit him with using a natural gas windfall to tackle poverty in one of South America's most deprived countries, and those who accuse his government of corruption and waste.
Critics say his attempt to change the constitution to allow him to stay in power until 2025 is anti-democratic.
Morales, Bolivia's first indigenous president, who was re-elected to a third term in 2014, says a "yes" vote is crucial to allow him to continue his social programmes.