Altamira, Brazil - A cluster of 12 men from the Xikrin tribe chant in their native language while marching together, arms interlocked, stomping their feet against the dry red dirt. They say this is their call of resistance from the Amazon.

The Xikrin are joined by about 150 indigenous people from three other tribes - the Arara, Juruna, and Parakana - that are occupying one of the work sites at the Belo Monte dam construction site in what is becoming a high-stakes standoff. The occupation, which is entering its second week, has halted a part of the construction on what will be the world's third-largest hydroelectric dam.

At the site of the protest, visited by Al Jazeera on Wednesday, the tribesmen were carrying clubs and spears and had built rudimentary sleeping quarters in what has essentially become a non-violent sit-in. An anthropologist was with them, typing away at her laptop as the indigenous people articulated their demands.

The tribes are occupying a road, built by the dam builders, which cuts through part of the Xingu River's waterways. The road blocks the natural flow of the waters.

Brazil tribes occupy hydroelectric dam project

The occupation of the site began at about 11 am on June 21 and played out like something from a fictional Hollywood movie. The indigenous people arrived at the work site in half a dozen small boats, charged the area, and announced that they were taking over. The construction workers, seeing the tribesmen with their faces painted for combat and armed with spears, immediately fled for safety.

"The workers were scared, so they immediately ran when we arrived," said Bepumuiti, from the Juruna tribe. "They probably thought they were going to die."

The tribesmen confiscated the keys to more than three dozen dump trucks and heavy machinery left behind.

What the indigenous people want

Last year, a series of conditions were agreed upon with the indigenous people to reduce the impact of the construction of the dam on their communities. Some of the conditions included the demarcation of indigenous lands, the construction of health facilities and schools, and means of transportation for the tribal people when the rivers dry up.

In exchange for their agreement, the indigenous said they would not forcefully oppose the dam construction.

The problem, the indigenous now say, is that while the construction of the dam steams ahead, the promises made by the consortium building the dam and by government-led Norte Energia - the energy company overseeing the dam - have yet to be fulfilled.

So the tribes decided to invade. This was a historic and significant move, because the decision was made without the assistance or knowledge of local or international NGOs or government rights bodies, who in the past often assisted tribes during protest movements.

"We would not be here today if the builders and the government would have done what they promised us," Bebtok, a tribe elder from the Xikrin tribe, told Al Jazeera. "In my community, nothing has been done. There is no quality health post, there is no school, they have not built a road for us. My road is the river and that is going to be dried up."

Since October, the tribes most affected by the construction of the dam have been receiving a budget of about $15,000 from the government, through which they can request anything they want, such as gasoline for their boats, food or construction material.

But the tribes have been told that the money - called "emergency assistance" in government parlance - will stop later this year, infuriating the tribal people at the very moment they are starting to feel the negative impacts of the dam, they say.

The indigenous people are now also starting to see the impact the construction is having on their lives. Surara, from the Parakana tribe, showed Al Jazeera how a road built on the construction site through a natural waterway of the Xingu river has already started to dry out one side of the river.

"We were always navigating this river because we know this river like the palm of our hands," Surara said. "And today, as you can see, it's very dry. That is sad for us."

Surara predicted that, at the current pace of construction, in two years the tribe will no longer be able to reach their community by boat because of the changes in water levels. The tribes have a new list of demands they want fulfilled before they say they will end their occupation.

Response from government and builders

The tribes' occupation of the dam seemed to catch the dam builders and the government by surprise. In response, Norte Energia has taken what seems like a peculiar approach that involves two very opposite responses, using the carrot and the stick at the same time. Three days after the occupation began, a judge rejected a request to have the indigenous evicted by force from the area.

Click here to see videos, in English, by Norte Energia about Belo Monte.

At the same time, Norte Energia is providing the indigenous people three meals a day at the occupation site. Often times, a representative from the company will show up at the site during a meal and ask the indigenous people for the keys back to their heavy machinery. So far, the tribes have refused to hand them over.

Last week, Norte Energia refused an Al Jazeera request for an interview on the matter. Norte Energia has said in the past that the economic and social assistance packages to help the tribes will be implemented at various points during the entirety of the project, as previously agreed upon.

Behind the scenes, the company is facing a daunting task. Not only do each of the four tribes involved in the occupation have their own set of demands, but there are also as many as 35 different sub-communities within the tribes taking part in the occupation, and each have their own interests and requests they want met.

Activists face arrest

Pressure is building on multiple fronts. Construction of the dam ramped up earlier this year, and there are strict timetables to get the dam up and running by late 2014.

Aside from the indigenous protest, several other tense issues surrounding the dam are coalescing at the same time.

In Altamira, the closest city to the dam site, 11 people - all unaffiliated with the indigenous protest now occurring - are fighting arrest warrants after being accused of helping organise an anti-dam protest earlier in June that the dam builders say led to property damage. Local TV channels have been airing video of broken windows and the burning of office equipment at the construction site.

The activists facing possible arrest all deny they were involved, and say any protests they organised were peaceful and legal. They include, among others, a Catholic priest, a nun, some members of Xingu Vivo Para Sempre - a local anti-dam NGO - as well as a local fisherman featured in an Al Jazeera report in January

Police have an open investigation, and have yet to formally announce if charges will be filed. However, even the threat of jail time has sent a chill through the tight-knit community of local anti-dam activists.

How will it end?

"As long as they don't do anything in our communities regarding infrastructure, we are not leaving the occupation." - Giliardi, Juruna tribe



On Thursday, in the city of Altamira, more than 60 of the indigenous occupiers met with a high-level delegation from Brasilia that included the president of Norte Energia.

The meeting lasted nearly four hours, and was closed to the media. The indigenous people discussed their demands to end the protest, but no agreement was reached. Norte Energia said they needed to take the requests back to Brasilia for analysis. A new meeting was set for July 9. In the meantime, the tribes say their occupation will continue. It was also agreed by all sides that work will continue on the parts of the construction site not under the control of the tribes.

"This was a very friendly conversation; the tribe elders are very wise and measured," said Carlos Nascimento, president of Norte Energia, in a brief press conference after the meeting. "There are some young tribesmen that want some improvements, and as much as we can, we will do anything in our power so these kinds of things will not happen again."

The indigenous seemed determined to keep up the fight for as long as it takes. "What we asked for, the dam builders did not give us an answer to, so we will only leave the construction site when they bring an answer to us on paper," Giliardi, from the Juruna tribe, said after the meeting. "And as long as they don't do anything in our communities regarding infrastructure, we are not leaving the occupation."

Meanwhile, more boats loaded with indigenous people are arriving at the protest site every day. It is an indication that this standoff in the Amazon could drag on for days to come.

Follow Gabriel Elizondo on Twitter @elizondogabriel

Follow Maria Elena Romero on Twitter @MarBrazil