Brazilian military police in front of Congress hurled tear gas at thousands of indigenous protesters, who responded by throwing spears and shooting arrows as a peaceful demonstration turned into chaos Tuesday. There were no reports of any injuries on either side. Police said protesters got too close to a large fountain of water on the esplanade in front of Congress in Brasilia, Brazil's capital.

The demonstration was peaceful until police blocked some of the indigenous people, their bodies painted and wearing colorful headdresses, from climbing a ramp that led into the congressional building, according to a Reuters photographer on the scene.

Demonstrators denied that, saying police were just looking for an excuse to remove them. They said that police had agreed the protesters could come close to the fountain and that the march was peaceful.

"Unfortunately, the brute force of the police caused this," said Kleber Karipuna, a protester who came to Brasilia from the northern state of Amapa. "It's natural that three thousand Indians are going to respond" with spears and arrows.

Protesters said at least four people were arrested in the clash. Police did not provide details.