Police and prosecutors from Brazil, French Guiana, Guyana and Suriname have arrested nearly 200 people in their first joint cross-border operation targeting illegal gold mining in the Amazon region, authorities said.

The operation was backed by Interpol, the EU and Dutch police specialising in environmental crime. It involved more than 24,500 checks on vehicles and people across remote border areas and led to the seizure of cash, unprocessed gold, mercury, firearms, drugs and mining equipment, Interpol said.

Among those arrested were three men detained in Guyana on suspicion of gold smuggling and money laundering after officers seized unprocessed gold and about $590,000 (£440,000) in cash. Investigators said the suspects were believed to be part of an organised crime group and may have links to a major gold exporting company in Guyana.

Illegal gold mining has become a major driver of deforestation and river pollution in the Amazon, contaminating waterways with toxic mercury and damaging lands relied on by Indigenous communities. In recent years the activity has expanded rapidly as global gold prices have climbed to near-record highs, pushing miners deeper into remote forest regions and turning gold into one of the most profitable commodities for organised crime operating across borders.

Interpol’s secretary general, Valdecy Urquiza, said in a statement: “Illegal gold mining is growing rapidly and causing serious harm to the environment and local communities, especially in remote and fragile areas.”

Authorities seized cylinders of mercury worth more than $60,000 in Guyana and Suriname. Mercury is commonly used in illegal gold mining to separate gold from other materials, but it is highly toxic and can contaminate rivers, wildlife and people. Interpol said the mercury had been hidden inside solar panels and transported by bus.

Police in South America carried out coordinated checks along shared borders, including inspections on both sides of rivers that separate the countries. Officers searched vehicles, boats and small riverside shops that sell fuel, tools and other supplies commonly used in illegal mining. Some of the shops are suspected of helping smuggle gold and mercury across borders.

During the operation, police also seized counterfeit medicines, alcohol and cigarettes worth more than $40,000, along with mining pumps, mats used to collect gold, firearms and mobile phones.

Authorities said officers stopped a bus carrying undocumented migrants, including several minors. Some of the children are suspected to be victims of forced labour or sexual exploitation, underscoring the human impact of illegal mining networks.

Interpol said the operation, known as Operation Guyana Shield, marked a significant step forward in cooperation between countries in the Amazon region, where dense rainforest, long distances and porous borders have long made it difficult to police illegal mining.