Dozens of indigenous protesters brandishing batons have forced their way into the venue hosting the Cop30 climate summit in Brazil.
Security guards clashed with a group of people who stormed the building in Belem on Tuesday.
The entrance to the venue was barricaded by security from the United Nations, who blocked the doors with tables.
Two security guards were hurt amid violent confrontations. A witness told Reuters that one guard was rushed from the scene in a wheelchair while clutching their stomach.
One guard with a fresh cut above his eye said he had been hit in the head by a heavy drumstick thrown from the crowd. Security confiscated several batons.
Shouting angrily, the protesters demanded access to the UN compound.
The group dispersed from the scene shortly after the clash on Tuesday evening, where world leaders are gathering to discuss climate change.
Delegates were allowed to exit the venue, having earlier been asked by security to move back inside until the area was clear.
