At least two people are confirmed dead from the collapse, which occurred late Sunday on the Juscelino Kubitschek de Oliveira bridge linking the states of Maranhao and Tocantins. When a section of the bridge went down, it took with it two cars, two motorbikes, and four trucks – two of which were carrying sulphuric acid, a police spokesman told AFP.

Their dangerous cargo prompted officials to pause the search operation early Monday. Water supplies to communities in the region were also suspended because of the possible “toxic” acid pollution, the spokesman said.

Brazil’s infrastructure and transport department said the causes of the collapse of the bridge, which was built in the 1970s, were being investigated. It said the central beam of the structure gave way. The collapse came on top of two other deadly transport accidents in Brazil over the weekend.