In the evening, Indigenous demonstrators and their supporters breached security barriers at the main entrance to the conference hall in Belem and scuffled with security officers there.

The incident caused "minor injuries to two security staff, and minor damage to the venue," a spokesperson for United Nations Climate Change told AFP.

"Brazilian and UN security personnel took protective actions to secure the venue, following all established security protocols," the spokesperson said.

Calm was quickly restored and security staff used tables and chairs to barricade the entrance to the high-level "blue zone" at the heart of the conference venue.

An AFP journalist saw a police officer being evacuated in a wheelchair.

Security inside the COP30 venue falls under the responsibility of the UN, while local authorities take charge of the surrounding area.

UN police officers were asking those still inside the COP30 venue to evacuate the vast site of giant air-conditioned tents.

"The Indigenous movement wanted to present its demands inside the blue zone but were not allowed in," said Joao Santiago, a professor at the Federal University of Para.

- 'Voices ignored' -

Maria Clara, a protester with the Rede Sustentabilidade Bahia association, told AFP she wanted to draw attention to the plight of Indigenous peoples.

"These voices are ignored," she said.

"They entered the COP30 venue to protest the fact that the COP will end but the destruction continues."

The March for Health and Climate, the organizers behind the protest, sought to distance themselves from the incident.

"The march, which concluded before the COP30 venue, was a legitimate, peaceful, and organized expression of popular mobilisation, built through dialogue, responsibility, and collective commitment," the group said in a statement.

The UN spokesperson said "the venue is fully secured, and COP negotiations continue." Brazilian and UN authorities were investigating the incident, the spokesperson added.

Last week, Brazil's Minister for Indigenous Peoples, Sonia Guajajara, said the UN summit would be "the best COP in terms of Indigenous participation."