JACKSONVILLE, Fla. -- Sheriff John Rutherford on Thursday announced the breakup of two drug rings that he said were bringing up to 100 kilograms of cocaine into Jacksonville every month.

Rutherford said "Operation Old Acquaintance" -- an 8-month investigation that involved local, state and federal law enforcement as well as police in Savannah, Ga., and Beaufort, S.C. -- broke up a drug distribution ring that was importing at least 50 kilos coming from Mexico, through Louisiana, Georgia and South Carolina to be distributed mostly in Jacksonville and Savannah.

In a separate, parallel investigation, other drug dealers were buying quantities of cocaine on the streets of Miami and reselling it on the streets of Jacksonville, Rutherford said.

"Any way you look at it, this city was under siege from cocaine from the north and south," Rutherford said.

The operation resulted in six arrests in Jacksonville, 11 in the Beaufort/Savannah area and three more in Miami. Other arrests are pending for seven others, including six people in Jacksonville and one person in Mexico.

"These are distributors -- these are not people selling small amounts," Rutherford said.

The operation, which the sheriff said brought in millions of dollars of cocaine, also resulted in the seizure of weapons, $165,000 cash and homes and vehicles in the Beauford area.

Rutherford said this was the largest drug bust in his history of the Beaufort, S.C., area.

Rutherford said cutting off two large streams of cocaine at the same time has resulted in a spike of the street price of cocaine.

"Fifty-five kilos bi-weekly -- that's a large dent," Rutherford said. "You can tell when you're really putting the pressure on the supply, it shows up in the price.

The operation's name, Old Acquaintance, comes from the fact that some of those involved in the two rings knew each other, some of theme meeting during previous prison sentences.