FTC accuses T-Mobile of knowingly billing customers for hundreds of millions in bogus charges.

The Federal Trade Commission is alleging that T-Mobile USA, Inc., made "hundreds of millions" of dollars off its customers through bogus charges.

In a complaint filed Tuesday, the FTC says the mobile phone provider billed consumers for subscriptions to "premium" texts such as $10-per-month horoscopes that were never authorized by the account holder. The FTC alleges that T-Mobile collected as much as 40 percent of the charges, even after being made aware that the subscriptions were scams.

FTC Chair Edith Ramirez said in a statement that the agency's goal is to ensure T-Mobile repays its customers. She said there were, quote, "clear warning signs the charges it was imposing were fraudulent."