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AT&T will have to pay $6.8 million to customers who were charged $9 per month for directory assistance services that turned out to be scams, the Federal Communications Commission said Monday.

The US Drug Enforcement Administration discovered the fraudulent charges while investigating two Cleveland-area companies for drug-related crimes and money laundering, the FCC said in a statement. Suspects told DEA agents "that the companies were set up to bill thousands of consumers (mostly small businesses) for a monthly directory assistance service on their local AT&T landline telephone bills," according to the statement. AT&T received a fee for each charge it placed on its customers' bills. However, the customers were never provided with directory assistance.

As part of the settlement with the FCC, AT&T will also pay a $950,000 fine to the US Treasury.