Federal authorities have been watching the baggage claim area at Tucson International Airport for the past three years, looking for passengers they suspect are working as money couriers for drug traffickers.
So far, those efforts have netted $555,000 in seized cash.
There have been 30 seizures at the Tucson airport since October 2014 by Drug Enforcement Administration agents.
The newspaper says the DEA agents didn't arrest anyone when they seized their money.
Instead, the agents handed the passengers a receipt and sent them on their way.
All but one seizure was done without a warrant. No drugs were found, other than small amounts of marijuana in two cases.