Bogota, Colombia ? A 100-foot, twin-screw diesel submarine seized at a jungle shipyard in Ecuador marks a quantum, if anticipated, leap in drug-smuggling evasion technology, the top U.S. counter-drug official for the region said Sunday.

Soldiers stand on a seized submarine Saturday in the jungle region of La Loma in Ecuador. U.S. officials said the diesel submarine was constructed in a remote jungle and captured near a tributary close to the Ecuador-Colombia border and is capable of transporting tons of cocaine. Ecuadorean authorities seized the sub before it could make its maiden voyage.

“It is the first fully functional, completely submersible submarine for transoceanic voyages that we have ever found,” Jay Bergman, Andean regional director for the Drug Enforcement Administration, told The Associated Press.

Until now, all the smuggling vessels seized on the high seas or at clandestine shipyards built to haul multi-ton loads of cocaine under the Pacific’s surface were semi-submersibles. They typically unload off Central America and Mexico drugs destined for the United States.

Equipped with air intake and engine exhaust pipes, none of those craft were capable of fully submerging so they could evade radar and heat-seeking technology of drug-interdiction aircraft.

The camouflage-painted vessel seized by Ecuadorean police Friday appears by contrast to be capable of long-range underwater operation — a development U.S. analysts have long expected, Bergman said.

Acting on a DEA tip, the Ecuadoreans found it at a sophisticated shipyard with living quarters for at least 50 people on a jungle estuary several miles from the Colombian border, he said. It had yet to make a voyage.

Built of fiberglass and other composites, it has a conning tower, periscope and air conditioning system and measures about 9 feet high from the deck plates to the ceiling, the DEA said. Ecuadorean police told the DEA the vessel has the capacity for about 10 metric tons of cargo, a crew of five or six people and the ability to fully submerge, Bergman said.

Compared with semi-submersibles, which cost less than $1 million each to build, “this is in a new maritime drug-trafficking class of its own,” Bergman told the AP.

He said U.S. nautical engineers would be taking the submarine apart in the next few days to determine its dynamics.

He said authorities are still investigating who financed the sub’s manufacture and which trafficking organization intended to use it.