MIAMI — The U.S. Coast Guard says a cutter patrolling eastern parts of the Pacific Ocean seized a “narco” submarine carrying cocaine worth a street value of more than $165 million.

In a Tuesday news release, the agency says the crew captured the self-propelled semi-submersible in international waters earlier this month and apprehended four suspected drug smugglers.

The semi-submersible was detected and monitored by maritime patrol aircraft and the Coast Guard cutter’s crew was diverted by the Joint Interagency Task Force South to seize it.

They offloaded about 1,100 pounds (500 kilograms) of cocaine but the rest couldn’t be safely removed due to concerns about the vessel’s stability.

A total of about 12,000 pounds (5,400 kilograms) was eventually seized.

Cmdr. Matthew Waldron says in a 24-hour period the cutter crossed the equator and intercepted the sub.