Workers at several jewelry shops are accused of helping Colombian drug lords launder money by molding gold into belt buckles, screws and other everyday items for shipment to the South American nation, The Associated Press reports.

Eleven workers at the stores, including six in the so-called Diamond District of midtown Manhattan, were arrested and charged with money laundering, federal authorities said Thursday.

The workers were arrested Wednesday after a two-year investigation found they had taken part in the money ring, U.S. Attorney James Comey said. They had not been arraigned as of Thursday.

“It’s incredibly important that we keep these drug dealers and their money on the run,” Comey told reporters. “They’re smart, but we’re smarter, and we work harder.”

Federal agents said the jewelry stores converted drug money into items that could be safely taken back to Colombia and then converted back into cash, the AP reports. Among those were diamonds and gold pieces that were melted down and molded into screws and tools, some of which were painted over to conceal them further.

JCK