Troops in Peru are patrolling towns in the nation's Amazon region to search for missing policemen after at least 60 people, mostly indigenous Indians, died in clashes over land development.
Forces controlled the town of Bagua Grande, about 1,400km north of the capital Lima, on Monday and imposed a curfew following the fighting, in which more than 20 police officers died.
Thousands of Indians, many armed with wooden spears, have vowed to continue their blockades on remote Amazon highways to defend their ancestral lands from outside developers.
Al Jazeera's Teresa Bo in Bagua says many protesters have taken refuge in a local Christian community centre while security forces try to find at least two police who remain missing, possibly taken hostage, along with weapons stolen by protesters.
There are also reports of many indigenous people missing, with local leaders saying many protesters cannot find their family members and fear that they are dead, she says.
Alan Garcia, the Peruvian president, blamed the deadly clashes on "foreign forces" in a comment widely thought to refer to neighbouring countries Bolivia and Venezuela.
"There is a conspiracy aimed at stopping us from using our natural resources for the good, growth and quality of life of our people," Garcia said on Sunday, blaming foreign interests that would benefit if Peru did not tap its gas and oil.
However our correspondent says locals disputed this claim, saying no foreigners were present during clashes. Many said they felt that the comments were an effort to diminish their protests.
Negotiations rejected
Champion Nonimgo from AIDESEP, Peru's leading indigenous rights group, ruled out dialogue with the government.
"We are dealing with a government that massacres Indians from helicopters. We are not going to hold talks under these conditions," Nonimgo said.
Indigenous tribes, worried they will lose control over natural resources, have protested since April to force the Peruvian congress to repeal investment laws passed last year that allow firms to drill for oil and mine resources in the jungle.
These latest clashes, the worst so far, began on Friday after about 400 police moved in to clear a road blocked by around 2,500 indigenous tribes people, some carrying spears and machetes.
The recent violence has highlighted deep divisions between elites in Lima and the rural poor, and threatened to derail the government's push to further open Peru to foreign investors.
Analysts say Garcia - whose approval rating is just 30 per cent - will probably have to fire senior cabinet members, including the prime minister, and roll back investment laws to end the stand-off.