Watch: 12,800 lbs. of cocaine seized from tiny semi-submersible

Coast Guardsmen seized more than 12,800 pounds of cocaine and apprehended four suspected drug smugglers from a self-propelled semi-submersible, or SPSS, about 300 miles southwest of Panama earlier this month.

The cocaine on board was worth more than $203 million.

The crew of the Coast Guard Cutter Bertholf from Alameda, California, was notified by a Customs and Border Protection aircraft about the SPSS.

Since June 2015, the Coast Guard says it has interdicted five SPSS vessels. The Coast Guard says these vessels are constructed for illicit trafficking because of their mostly-submerged hull. The cockpit and exhaust pipe are visible just above water.

These vessels are extremely difficult to detect and interdict because of their low-profile.

You can watch video, courtesy of the Coast Guard Pacific Area Command, of the seizure in the video player above.

Editor's Note: The video does not have audio.