Twenty-two people conspired for a decade to fly cocaine from California to Pittsburgh while bypassing airport security measures but lost a drug-filled bag when it was mistakenly unloaded during a layover, federal authorities say.

A federal grand jury indictment, returned in June but revealed only Wednesday by the U.S. attorney in Pittsburgh, charges 17 people from California, four from Pennsylvania and one from Maryland. The Associated Press couldn't immediately access the document because it hadn't been docketed, but a spokeswoman for the prosecutor's office and a news release provided some key details.

Timothy White, of Tracy, Calif., was identified as one of the "primary sources" of the cocaine and was accused of employing couriers who would travel to the Pittsburgh area with the cocaine and then travel back to California with money from drug sales.

"White had the ability to bypass airport security in order to transfer the cocaine to the couriers," the news release said.

U.S. attorney's office spokeswoman Margaret Philbin couldn't explain how that happened, and prosecutors on the case weren't available for comment Wednesday.

Another man, Ruben Mitchell, of Stockton, Calif., lost track of more than 40 pounds of cocaine in a misdirected piece of luggage during a Pittsburgh-bound Southwest Airlines Inc. flight last year, prosecutors said.

Mitchell had the drugs in a carry-on bag when he boarded the flight on Feb. 19, 2009, but a flight attendant put the bag in the plane's cargo hold because it wouldn't fit in an overhead luggage compartment, they said. The bag then was mistakenly unloaded during a layover in Las Vegas, and Mitchell later filed a lost-baggage claim for it after arriving in Pittsburgh, they said.

Authorities didn't immediately say whether the loss of the bag or other incidents led them to uncover the operation. But, according to the press release, Drug Enforcement Administration and Internal Revenue Service agents executed search warrants at homes in California and the Pittsburgh area in February this year.

White, 40, and Mitchell, 42, remained in custody Wednesday. Fifteen other people have been arrested, though some have been freed on bond. Five remain at large.

Twenty-one defendants each face up to life in prison and an $8 million fine if convicted. The other faces up to 20 years in prison.

Online federal court records don't list defense attorneys for the suspects. Prosecutors said White fired his initial attorney and they don't know who represents him now. Mitchell's defense attorney, federal public defender Elisa Long, of Pittsburgh, didn't immediately return a telephone call seeking comment Wednesday.

The California defendants are primarily from northern cities of Oakland, Stockton and San Jose, while the Pennsylvania defendants are from Pittsburgh or nearby suburbs. The remaining defendant is from Frederick, Md.