The National Department of Transport Infrastructure said the central span of the 533-meter (0.3-mile) bridge, linking the cities of Estreito in Maranhao state and Aguiarnopolis in Tocantins state, gave way in the afternoon. A tanker truck carrying the acid plunged into the water, officials said.

According to the fire department, one person has been confirmed dead and another was rescued alive.

Aguiarnopolis city councilman Elias Junior was recording a video asking authorities to fix problems with the bridge, which he said could no longer handle the heavy trucks passing over it. As he pointed to a large crack on the shoulder of the bridge, the structure collapsed in front of him, causing him to run back. Reuters could not immediately independently verify the video. Junior did not immediately respond to a request for comment.

Preliminary estimates indicate at least 11 people were involved in the accident with two trucks, a car, and a motorcycle falling into the river, which is more than 50 meters (164 feet) deep.

By early evening, rescue divers halted their efforts after identifying that one submerged tanker was leaking sulfuric acid, said the fire department from Tocantins.

The Juscelino Kubitschek de Oliveira Bridge, inaugurated in 1960, was built with reinforced concrete and is part of the BR-226 highway, connecting the federal capital Brasilia to Belem, a northern city set to host the United Nations Climate Change Conference next year.