U.S. Customs and Border Protection officers seized more than 3,000 lb. of methamphetamine valued at nearly $5 million at the Otay Mesa Commercial Facility in San Diego.

The drugs were discovered April 14 inside a cargo trailer hauling what was declared as corrugated cardboard boxes.

Officers referred a 2017 Freightliner Cascadia and its trailer, along with the 31-year-old driver, a Mexican citizen, for secondary inspection. A nonintrusive scan identified anomalies in the trailer’s front wall, and a canine unit alerted to the same area.

A subsequent physical inspection uncovered 300 packages of a crystal-like substance wrapped in plastic. The load tested positive for methamphetamine and weighed 3,078 lb.

“Our CBP officers at ports of entry are unwavering guardians,” said Rosa E. Hernandez, Otay Mesa port director. “Their diligence prevented illegal narcotics from entering our country, so our communities are kept safe from dangerous drugs.”