HUANUNI, Bolivia (AP) -- The Bolivian government deployed 700 additional police to quell a deadly clash that flared anew on Friday as rival bands of miners hurled dynamite at one another in a battle over one of South America's richest tin mines.

Officials say at least 11 people have been killed and more than 50 injured in fighting between independent miners' cooperatives allied with President Evo Morales and miners employed by Bolivia's state mining company.

A truce on Thursday night lasted just long enough for both sides to bury their dead.

But at dawn Friday, hostilities renewed on the barren slopes of Posokoni Mountain, which looms over this small mining town 290 kilometers (180 miles) south of the capital of La Paz. Miners from both sides threw dynamite and homemade explosives at each other from ridge to ridge, sometimes separated by no more than 50 feet (15 meters).

Miners, some only in their teens, carried sticks of dynamite in backpacks and tucked in their belts.

In town, residents held a prayer vigil in the local church for the violence to end. Blood stains and holes from explosives littered a soccer field in the Dolores neighborhood following fighting there Thursday.

On Friday morning, members of the miners' cooperative rolled three tires packed with explosives down the side of the mountain toward town, causing an enormous explosion.

Bolivia's National Police Commander Isaac Pimentel told a news conference that 700 more police would be sent to the area, but Government Minister Alicia Munoz added shortly afterward that the police would not carry lethal weapons.

Overnight talks led by senior government officials failed to achieve a lasting agreement. Defense Minister Walker San Miguel blamed "intransigents that have not signed on to the cease-fire," but said he hoped the rivals might return to negotiations.

"We do not believe the doors of dialogue have been shut," he said.

Jerson Mollinedo, director of the state-employed miners' union, said his group wants peace, but not at any price.

"We don't want any more orphans," he said. "But we will not surrender even a millimeter to the cooperatives, because as a business we too want to employ our fellow workers."

The conflict turned deadly on Thursday morning, as hundreds of miners belonging to independent cooperatives stormed the state-owned Huanuni mine, demanding more access to its tin deposits. State-employed miners counterattacked to regain control of the mine and the groups exchanged gunshots and flying sticks of dynamite.

"It rained dynamite," independent miner Felix Condori told The Associated Press.

More than 4,000 members of miners' cooperatives have descended on Huanuni, with more expected to arrive to battle the roughly 1,000 state-employed miners.

Morales was elected in December with a mandate to help Bolivia's poor indigenous majority see a larger share of the revenues from the landlocked nations' extensive mineral and natural gas deposits.

The cooperatives strongly backed Morales' campaign last year, and the president has since granted them some concessions at Huanuni.

"What should have been a blessing for the country, to possess such natural riches, today has become a curse," Vice President Alvaro Garcia Linera said in a national address Thursday evening.

While the Bolivian government so far declined to mobilize the military in response to the conflict, about 70 soldiers already stationed in Huanuni spent the night guarding the offices of Comibol, the national company operating the mine.

Among the dead were men and one woman from both miners' groups, as well as a local bus driver. Presidential spokesman Alex Contreras read the names of the dead on national television Friday morning.

The battle for Huanuni has roots going back at least 20 years. In 1985, Comibol shuttered mines throughout Bolivia after a collapse in the world metal market, laying off some 30,000 workers.

While many of Huanuni's unemployed miners sought work in other fields and other parts of the country, some remained, and as prices recovered, they formed independent mining cooperatives to mine tin on their own.

Bolivia eventually granted the Huanuni mine concession to British-based Allied Deals. When the company, now known as RBG Resources, abandoned its Bolivian operations in 2005, the mine returned to Comibol, despite demands from the miners' cooperatives for some control over the valuable deposits.

Rising tin prices have stoked demands by the independent miners, who see the Huanuni vein as a rare source of steady employment in South America's poorest country.