DENVER -- A California man was arrested after sheriff's deputies said they found almost 8 pounds of methamphetamine in his car Tuesday morning.

Alonso Verdugo-Moreno, 45, was driving along Interstate 70 near the Utah state line when he was pulled over for speeding, said spokeswoman Heather S. Benjamin of the Mesa County Sheriff's Office.

According to the arrest affidavit, when deputies questioned Verdugo-Moreno, he "appeared to be very nervous and his hands here visibly shaking." When the trooper asked him about his travels, Verdugo-Moreno appeared hesitant and uncertain.

The trooper asked to search his car and a search dog pointed to the rear passenger seat, the affidavit said.

Deputies found a metal panel behind the seat with heavy tooling on the bolts, the affidavit said. When they removed the plate, deputies found six cylindrical packages wrapped in cellophane which later tests were confirmed to have meth.

Verdugo-Moreno is being held at the Mesa County Detention Facility on a $510,000 bond.