They say they found 2,400 pounds of marijuana and more than a million dollars in cash inside two houses.
The houses allegedly are linked to a Mexican drug cartel. Sean Clark and his friend say they saw the whole thing.
"They opened the garage and there was up to the ceiling in bags of pot. It was crazy," Clark said.
Police arrested four people.
They say the drug trafficking ring used Louisville as a smuggling pipeline.
The bust was the result of an eight month long investigation.
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