fter noticing plastic tubes bobbing above the ocean's surface, U.S. Coast Guards seized a makeshift submarine transporting 3.5 tons of cocaine across the Pacific Ocean.

After spotting the suspicious water craft, officials took the submarine to a Costa Rican Coast Guard station to determine its origins. The vessel, which was found with several tanks of gas, had likely traveled hundreds of miles on its way to the U.S.

Three Colombians, a Guatemalan and a Sri Lankan, who were breathing through pipes fastened inside the 50-foot wood and fiberglass submersible craft, were all reportedly arrested and taken to the United States for prosecution.

The U.S. Coast Guard frequently patrols for drug shipments off Costa Rica, with Costa Rican authorities seizing 18 tons of cocaine so far this year.