A group of activists skirmished with security on Tuesday at United Nations climate talks in Brazilian Amazon city Belem, briefly trying to force their way into the main venue before they were pushed back.

Fred Almeida, an eyewitness, and others described seeing the confrontation late in the day as people were filtering out of the venue. It wasn't immediately clear if anyone was hurt.

Associated Press journalists inside the building saw a line of security keeping people from entering.

Brazilian and UN security personnel took protective actions to secure the venue, following all established security protocols. Brazilian and UN authorities are investigating the incident. The venue is fully secured, and COP negotiations continue, according to a spokesperson for UN Climate Change.

(AP Video by Joshua A. Bickel)

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