MIAMI (AP) _ A South American air cargo carrier was fined $640,000 after inspectors found 40 pounds of cocaine aboard a jet at Miami International Airport, a Customs spokesman said Sunday.

The cocaine was in a cardboard box not listed on the manifest Saturday of an Ecuatoriana Air Cargo flight from Ecuador, said Customs spokesman Cliff Stallings.

The carrier was fined $640,000 under a 1986 law allowing fines of $1,000 per ounce of any illegal drug cargo. The law also permits seizure of the plane but that was not done, Stallings said.