Bangladesh, Sept. 30 -- A sweeping European law-enforcement operation has dismantled an alleged criminal network accused of turning millions of used mobile phones into a highly profitable fraud business, selling refurbished or reconstructed devices to consumers across the European Union as supposedly brand-new products.

The operation, code-named "Troja," was led by the European Public Prosecutor's Office (EPPO) and resulted in the arrest of seven suspects, including two people prosecutors identify as alleged ringleaders. More than 1,700 law-enforcement officers participated in the coordinated action, carrying out more than 160 searches across 19 countries.

According to prosecutors, the suspected network generated hundreds of millions o...