Ottawa ? The Franklin County sheriff’s office says it executed what could be one of the state’s largest seizures of drug sales proceeds.

Franklin County authorities were still counting the cash Thursday. It was recovered Tuesday from a semitrailer at a rest area on Interstate 35 south of Ottawa.

Sheriff Craig A. Davis said authorities were checking the rest area with a police dog when they met Carlos Angelo, a Mexican national. After receiving permission to search his truck, officers uncovered the cash.

Davis said Angelo denied knowledge of the money. He is in the Franklin County Jail until officials from U.S. Immigration and Customs Enforcement arrive.

The largest cash seizure from drug sales in state history occurred in January 2000, when the Colby Police Department found $3.7 million in a rental car stopped for a traffic violation.