Federal agents Tuesday conducted several raids in the Detroit area in an investigation of illegal money transfer operations.
The transfers may have sent up to $50 million a year to Yemen.
Seven people were arrested, six on warrants and one on an immigration violation. They were expected to appear in court later Tuesday, when the warrants will be unsealed.
U.S. Customs agents seized records and computers from some of the businesses, which included convenience stores, service stations and restaurants. Five seizure warrants were issued for banks in the Detroit area and Toledo, Ohio.
The raid netted more than $200,000 from the bank accounts, a handgun and more than 20 pounds of khat, a popular African stimulant that is either chewed or brewed into a tea.