The government of President Evo Morales carried out a bloody crackdown Sunday against a march by indigenous protesters against the building of a new highway through their lands.

Some 500 paramilitary police surrounded the encampment of the thousand or more marchers, including hundreds of women and children, firing teargas, beating the protesters with clubs and fists, trampling many and handcuffing them and throwing them face first onto the ground.

The assault killed a three-month-old baby, who died of asphyxiation from the teargas. Many others were injured, and at least 37 were reported missing, including a number of children.

The surprise attack came on the same day that Morales had announced his intention to put the highway project to a referendum in Beni and Cochabamba, the two departments through which it would pass, and invited leaders of the march to meet with him in the government palace.

A police commander justified the violent attack by saying that the Indians had placed police in danger by carrying bows and arrows. They also referred to the alleged “kidnapping” the day before of Bolivian Foreign Minister David Choquehuanca, who was sent to initiate a dialogue with the protest leaders. Apparently, Indian women had taken Choquehuanca by his arms and persuaded him to march with them. He later claimed that he was used as a “human shield” to break through a police attempt to blockade the march.

The police had aimed to round up the protesters, load them onto planes and fly them back to where they had started. This plan was disrupted, however, when hundreds of outraged residents of the town of Rurrenabaque, near where the police assault took place, occupied the local airport’s runway blocking planes with tree trunks and burning tires. The residents surrounded the buses in which the demonstrators were being taken to the airport, chased away the police and freed their hundreds of captives.

In La Paz, Interior Minister Sacha Loretta claimed that the police had decided to free the detainees “to prevent confrontation.”

The march had begun 41 days earlier in the northern city of Trinidad. Its objective was the capital of La Paz, 500 kilometers (310 miles) to the southwest, where the marchers intended to protest the planned highway, which would be built through the Isiboro-Secure Indigenous Territory and National Park, known by its Spanish acronym, TIPNIS.

The preserve includes 3,860-square-mile of Bolivia’s Amazon basin and is inhabited by some 50,000 people from three different Amazonian Indian groups that have inhabited the area for centuries. It is the center of much of Bolivia’s biodiversity as well the source of much of the country’s water.

The crisis the confrontation has created for the Morales government became evident with the resignation Monday of the Bolivian defense minister, Cecelia Chacon. “I do not agree with the intervention in the march and I cannot justify the measure when other alternatives existed,” she wrote in a letter to Morales.

Meanwhile, hundreds of members of other indigenous groups have launched protests, including hunger strikes in Santa Cruz and Cochabamba and a vigil in La Paz. And the country’s union federation, the COB (Bolivian Workers Central), has called a general strike on Wednesday in support of the Amazonian Indians.

Morales, who was first elected president in 2005 as the leader of the Movement Towards Socialism party, or MAS, has described himself as Bolivia’s first indigenous head of state. He oversaw the rewriting of the country’s constitution to declare Bolivia a “plurinational state” and to grant a degree of political and cultural autonomy to the indigenous peoples.

From the outset, however, the name of his party notwithstanding, the Morales government has pursued a policy of promoting capitalist development both by extending concessions to foreign capital and defending the interests of the native bourgeoisie. The government has described its policy as “Andean-Amazonian capitalism.”

While initially able to win popular support through the introduction of modest social assistance programs, made possible by rising prices for Bolivian exports, over the past year it has confronted a series of general strikes and social protests fueled by soaring food prices, stagnant wages and cuts in government subsidies.

The government has attempted to mobilize indigenous groups in its support, denouncing the Bolivian workers fighting for increased wages as a “special interest” group.

Now, with the protest by the Amazonian Indians, it has tried to dismiss their struggle as an instrument of the Bolivian right and the US Embassy aimed at “defending capitalism.”

In reality, the proposed highway, touted by the Morales government as a means of developing the country’s poorer areas, is another manifestation of the overwhelming subordination of Bolivia’s economy to the interests of Brazilian capital. It is being financed by Brazilian loans and built by a Brazilian company. Its primary purpose will be to create a route for Brazilian exports, particularly soya, to the Pacific ports of Chile and Peru and, from there, to the Asian markets.

The greatest fear of the Amazonian Indians is that the highway will open up their region to exploitation for lumber and by landless Bolivians from the highlands seeking new areas to cultivate the country’s most profitable crop, coca.

The government of Morales, who was himself the former president of the cocaleros, or coca growers, union, has evidently sought to whip up support among the government’s supporters among the highland indigenous groups that have sought to farm in the Amazon area. A few dozen of them tried to block the march with barricades.

This led Foreign Minister Choquehuanca to warn of potential violence between different indigenous groups and even compare it to the genocidal conflict between Hutus and Tutsis that claimed the lives of hundreds of thousands in Rwanda.

In reality, the brutal attack on the Amazonian Indians has been condemned by representatives of indigenous peoples throughout the country. “We feel ashamed of what is happening in our country,” said Reynaldo Flores, a spokesman for the group on hunger strike in Cochabamba.

Waldo Albarracin, the country’s former public defender, told the AFP news agency that Sunday’s police violence represented “a reprehensible act of political repression similar to those unleashed by the de facto governments” that ruled Bolivia under military dictators in the 1960s and 1970s.