(CNN) - It started when police found nearly $7.2 million stuffed in eight suitcases at a Panama airport.
Investigators say they suspect the cash, which had been concealed in hidden compartments in luggage on a flight from Honduras, was being moved for a powerful cartel, but they haven't said which one.
The money was mostly in U.S. $100 bills, authorities said.
In a case that highlights the regional impacts of the drug trade, now Honduran investigators are trying to figure out how the suitcases slipped by airport authorities, drug police and special investigators at the Toncontin airport in Tegucigalpa.
Authorities have suspended dozens of officers as they investigate, Honduran police told CNN affiliate Televicentro.
Panamanian police, who described the suitcase stash as their largest seizure in years, arrested three Honduran nationals at Tocumen International Airport.