SAO PAULO, Brazil — A group of wildcat miners blocked a highway that cuts through the Amazon this week to protest a government crackdown on illegal mines, in the latest challenge to President Jair Bolsonaro amid growing international pressure to protect the rainforest.

Thousands of illegal miners operate in the Amazon, often digging up sparsely populated indigenous reserves and national parks for gold and diamonds.

Now the miners are demanding that Bolsonaro, who was elected on a promise to open up the Amazon for business, come to their defense. Environmental protection agents this week destroyed excavators and tractors found at an illegal mine in a national forest. Videos of the equipment on fire quickly spread across social media. 

“Look, that’s an order from our president, Jair Bolsonaro,” one miner said in a video widely shared on messaging apps here. “They are burning the workers’ equipment.”

The damage, the miner said, would cost him $200,000.

Bolsonaro won the backing of Brazil’s powerful agricultural lobby last year in part on promises to limit indigenous rights and expand development in the Amazon. In April, his administration said the government would no longer burn mining and logging equipment seized in raids of illegal operations. Agents had destroyed the equipment to prevent new mines from sprouting elsewhere.

“You are not to burn anything — machines, tractors, whatever it may be,” Bolsonaro said in a video posted to social media in April. “That is not the protocol. That is not the order.”

But that was before the world started watching. 

An international backlash against Bolsonaro’s allegedly lax environmental oversight in the Amazon spiked with the fires in the rainforest last month, dealing the president his biggest crisis since he took office in January.

Deforestation under Bolsonaro has nearly doubled, according to the country’s Space Research Institute. Forest fires have surged. An international outcry over the destruction has led to boycotts of Brazilian leather abroad and jeopardized an important trade deal with Europe.

Bolsonaro, caught between domestic calls for looser environmental regulation and global demands that Brazil preserve the rainforest, has dodged calls for international intervention while quietly increasing raids. 

The president sent 800 soldiers and agents to the region to extinguish fires and look for illegal activity.

Tensions between environmental protection agents and farmers, loggers and miners in the region are rising. About 250 miners blocked traffic on a highway Monday and demanded a meeting with Environmental Minister Ricardo Sales to legalize their mines.

Environmental protection agents who uncovered an illegal mine at an indigenous reservation were shot at last week.

The miners say they feel betrayed by the administration they helped elect.

“You said this wouldn’t happen anymore,” one miner said in a message posted online. “I wish, Bolsonaro . . . that you could see this video and explain to Brazil why this is happening.”

Bolsonaro is trying to lift Brazil out of years of economic stagnation. Nearly 13 million people are unemployed, and in the Amazon, where jobs are scarce, mining is increasingly attractive. 

Bolsonaro said throughout his campaign last year that he wanted to tap into the riches of the Amazon to spur economic growth. He promised to open indigenous lands for mining.

Mining in indigenous reserves remains illegal, but critics say Bolsonaro’s comments effectively encouraged invasions of tribal land. Greenpeace Brazil estimates that there are mines in 18 indigenous territories. 

“Miners are workers, people who unfortunately live on the margins of society,” said Danicley Aguiar, a member of Greenpeace’s Amazon campaign. “But this is not how you fix their lives. They need economic growth and the creation of formal jobs.”

For tribal members who live in the reserves, Aguiar said, mining has brought violence, disease and destruction. In July, illegal miners invaded the Waipi-Apina tribal land in the eastern Amazon and killed a tribal chief.

“For indigenous people, these mines are a death sentence,” Aguiar said. “If indigenous land were to be open for mining, it would mean the complete destruction of their political and social organization and the ecosystem in which they live.”