In any event, the ever-changing tactics of Colombian drug traffickers targeting the lucrative U.S. market reflect a constant cat-and-mouse game.

"When we adjust to them, they adjust to us," said Rear Adm. Joseph Nimmich, commander of the Key West, Fla.-based Joint Interagency Task Force South, a multinational force set up to interdict oceangoing drug shipments.

"Their reaction to our greater surveillance and increased interdictions has been these self-propelled submersibles."

Are drug cartels resorting to submarines out of "desperation or just diversification? It's a combination of the two, with the greater emphasis on the former," said Assistant U.S. Atty. Joseph Ruddy, who heads Operation Panama Express, a Tampa, Fla.-based task force. The task force's interdictions have resulted in more than 1,100 drug traffickers being convicted since 2000.

The boats seized Oct. 28 are submarine-like, but officials here say a more accurate description is "self-propelled semi-submersible" craft because they do not dive and resurface like a true submarine.

Submarines are not new to drug trafficking, only more numerous, if the increase in seizures is any indication.

In what was the most spectacular bust involving a narco-submarine, police in September 2000 raided a warehouse near Bogota, the capital, and found a 100-foot-long submarine that was being built according to Russian plans.

The sub was thought to be a joint venture by Colombian and Russian drug mafias and would have been capable of carrying 10 tons of cocaine per trip had it been completed. Annual Colombian cocaine production is now estimated at 500 to 800 tons.

In 1995, police broke up a deal in which Colombia's Cali cartel had planned to buy a Russian submarine.

The know-how to build crude "submersibles" is readily available on the Internet and in back issues of Popular Mechanics magazine.

Hobbyists in the United States have formed the Personal Submersibles Organization; they conduct chats on the group's website, psubs.org, and hold annual meetings.

But the vessels found on Colombia's Pacific shores last week were built for anything but recreation and certainly not by hobbyists.

The Colombian coast guard official said crew members of a submersible detained this year after their 55-foot vessel sank off the coast of Tumaco, Colombia, told police that they viewed the craft as a death trap but were lured by the $2,000 payment the drug magnates promised to pay them to guide the vessel to Central America.

Asked to describe the men detained, the coast guard official merely said: "Crazy."

chris.kraul@latimes.com