Saturday's prescription drug take back collected more than 10,000 pounds of medication, the Drug Enforcement Administration said.
Residents disposed of 5 tons of drugs at more than 90 locations in Arizona.
The DEA has held five other take back events. All told, more than 58,000 pounds, or 29 tons, of prescription drugs have been removed from circulation.
The events are a big piece of the White House's prescription drug abuse prevention strategy released in 2011 by the Office of National Drug Control Policy.
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