Law enforcement agencies from around the globe arrested 288 people suspected of buying or selling drugs on the dark web. In a pair of press releases posted on Tuesday, the US Department of Justice and Europol said the joint effort also resulted in the shutdown of the dark web marketplace, Monopoly Market.

The operation, codenamed SpecTor, was done in collaboration with nine countries, including the US, UK, Austria, France, Germany, the Netherlands, Poland, Brazil, and Switzerland. While 155 of the arrests took place in the US, authorities seized $53.4 million in cash and digital currencies, 850kg (or 1,873 lbs) of drugs, and 117 firearms worldwide.

Monopoly Market has been on the dark web since 2019 and has since served as a hub where criminals can buy and sell drugs, according to CyberScoop. German authorities brought down the site’s criminal infrastructure in 2021, Europol notes, which served as the “basis for hundreds of national investigations.” Law enforcement also obtained the buyer lists from the site’s illegal vendors, potentially resulting in “thousands” of more arrests across the world.

“Operation SpecTor was a coordinated international law enforcement effort, spanning three continents, to disrupt drug trafficking on the dark web and represents the most funds seized and the highest number of arrests in any coordinated international action led by the Justice Department against drug traffickers on the dark web,” said US Attorney General Merrick B. Garland said in a statement.