Authorities are investigating how $12.5 million dollars of cocaine ended up inside an 18-wheeler coming into the United States from Mexico.

U.S. Customs and Border Protection (CBP) officers told Action 4 News that the seizure happened at the Pharr-Reynosa International Bridge on Thursday.

Customs officer reported that the 18-wheeler came into the United States from Mexico but was sent to secondary inspection.

Authorities reported finding 150 packages with about 392.2 pounds of cocaine worth $12.5 million dollars hidden inside the structure of the trailer.

No arrests were report but the case remains under investigation by federal officials.