As the chief courier of a California-to-Ohio marijuana shipping scheme pleaded guilty Friday, prosecutors said the investigation continued into other possible suspects in the plot that brought hundreds of pounds of marijuana hidden in suitcases to Ohio on private jets.

Authorities say Lisette Lee was the primary courier for a scheme that distributed about 7,000 pounds of the drug and made more than $3 million from November 2009 through April.

"Obviously other people were involved in the case," assistant U.S. attorney Tim Pritchard said after Lee pleaded guilty. "We're continuing to look as we were from the first day."

Lee, 29, pleaded guilty to one count of conspiracy to distribute and possess with intent to distribute more than 2,000 pounds of marijuana. She faces 10 years to life, though under federal sentencing rules she's likely to receive the lower sentence.

Frank Edwards, of Hacienda, Calif., was among five others arrested in the case. He pleaded guilty Friday to a similar charge involving more than 200 pounds of pot. He faces five to 40 years in prison, but also is not expected to receive the longest term.

Lee recruited Edwards, 40, to act as a courier and he was not involved in obtaining or distributing the marijuana, according to testimony Friday by Matthew Heufelder, a U.S. Drug Enforcement Administration special agent.