A Florida-based Customs and Border Protection aircraft recently intercepted a semi-submerged smuggling vessel filled with five metric tons of cocaine.

The Air and Marine crew tracked the self-propelled vessel carrying $352 million worth of cocaine and coordinated a plan with the U.S. Navy and U.S. Coast Guard to intercept the vessel. Four suspected smugglers were taken into custody.

The Customs and Border Protection aircraft was patrolling in the eastern Pacific Ocean when the crew spotted the vessel Sunday during an ongoing western hemisphere tracking operation.

The aircraft sent instructions to a U.S. Navy ship to meet the vessel. Coast Guard members arrested the suspects and seized 11 cocaine bales.

CBP’s operation includes P-3 Orion long-range surveillance and patrol aircraft throughout the United States, Central and South America to purse threats.