* Consortium stops work after workers set fire to vehicles
* Belo Monte to be world's third largest hydro-power dam
* Dam on Xingu river set to start operations as early as 2015
BRASILIA, Nov 13 Work on the world's third largest hydroelectric dam was halted this week deep in the Amazon jungle after workers set fire to vehicles and smashed computers during labor talks, the consortium building the Belo Monte dam said.
The controversial $13 billion project is opposed by environmentalists and Amazon natives who will be displaced by the 11,200 megawatt dam. Now it has been hit by a labor dispute.
CCBM, as the consortium is known, decided to halt work by 15,000 workers on Monday after workers vandalized offices and canteens, set fire to mattresses, burnt a bus to the ground and blocked the Trans-Amazon highway, the consortium said in a statement.
The violence began after hooded workers disrupted contract negotiations between the company and the main labor union on Saturday night, and continued into early Monday.
"We had to stop work for the security of the workers," said CCBM spokesman Fernando Santana by telephone from Altamira, where the dam is build built on the Xingu river.
The three construction sites in Altamira were calm on Tuesday, but work would not resume until the consortium is sure there is no further violence, Santana said.
In October, one of the sites was paralyzed for 10 days by Amazon natives and local fishermen demanding more compensation for communities affected by the dam project.
Belo Monte will be the world's third biggest hydroelectric dam after China's Three Gorges and Itaipu, on the border of Brazil and Paraguay. At one of the sites halted on Monday, workers are excavating a 20-km (12.4-mile) canal that will involve removing more earth and stone than was removed to build the Panama canal.
The dam has been criticized by conservationists because it will flood a large swathe of Amazon rainforest.
Brazilian President Dilma Rousseff approved the dam project, arguing that the world's sixth largest economy needs more hydroelectric generating capacity to cover rising energy consumption by an expanding middle class consumer society.
The Norte Energia consortium that owns the concession for the dam, which is set to start producing electricity in 2015, includes utilities Eletrobras, Cemig and Light. (Reporting by Anthony Boadle; Editing by Jackie Frank)