The Brazilian government has launched its biggest ever operation to remove thousands of cows owned by illegal land grabbers from indigenous territory in the Amazon rainforest.

Three helicopters, a dozen vehicles and a heavily armed corps of police and environment rangers are carrying out the cattle drive, which criminal gangs attempted to block by setting fires on the route, destroying bridges and intimidating drivers.

Operation Eraha Tapiro (“Ox Removal” in the language of the Assurini Indigenous people) aims to restore state control over the Ituna-Itatá Indigenous Territory, which suffered some of the worst deforestation and invasions in the Amazon during the previous presidency of the nationalist Jair Bolsonaro.

Since a change of power at the start of this year, the leftwing president, Luiz Inácio Lula da Silva, has promised to curb environmental crime, halt the expansion of the agricultural frontier and aim for zero deforestation by 2030. The environment minister, Marina Silva, has launched a series of operations to drive illegal miners and ranchers out of indigenous territory and other public lands that are under the protection of the state.

The operation commander, Givanildo Lima, who is an agent for the government’s main environmental protection agency, Ibama, said this was a politically symbolic operation on the frontline of environmental crime in the Amazonian state of Pará.