Tsalickis had built a tourist empire in the isolated town, carved from the jungle of the remote southern tip of Colombia.

"He was sort of the godfather of Leticia," said a U.S. official in Bogota.

The 61-year-old American owned a hotel, a small zoo of tropical animals near the edge of town, a tourist lodge on Monkey Island in the Amazon River and a firm that exported exotic animals and tropical hardwoods to the United States.

But, U.S. officials say, Tsalickis also exported something else: cocaine.

He was arrested in Florida last year after a tip led authorities to 7,300 pounds of cocaine hidden in hollowed-out Brazilian cedar brought to the United States aboard a freighter used in his export business. The seizure was described as the second largest in U.S. history.

The "godfather of Leticia," linked by U.S. authorities to a pair of Colombian drug cartel members, was convicted in federal court and sentenced to 27 years in prison.

In Tsalickis' absence, his tourist empire has fallen into ruins.

His lodge on Monkey Island has closed. So has the zoo. The hotel in Leticia is still open, but it is falling apart and has few guests.

His red-brick house and adjoining bar, just a block from the Amazon River, were seized in August when the government began its war against the cocaine cartels by confiscating the property of suspected drug traffickers.

The seizures were only the latest blow local officials say they have struck in breaking the stranglehold that drug barons held on Leticia a few years ago.

The town lies at the intersection of Colombia, Brazil and Peru, smack in the middle of the world's greatest cocaine-smuggling route.

"This town used to be a strategic point in the drug traffickers' network, but not anymore," said Fausto Dosantos, mayor of the city of 28,000 people. "We don't want to remember those old days. That was a sickness that has gone long ago."

Leticia seems made to order for drug smuggling. The borders go largely unpatrolled. Not one of the three countries operates radar to detect aircraft in the region, known locally as Amazonas.

"You have to understand that the terrain here in Amazonas is immense," said Brig. Gen. Augusto Rodriguez, who heads the Colombia Southern Command, based in Leticia.

"There are no highways. The only way in is by air or by river. It's very difficult to control. People can easily get in and out without detection."

Founded in 1867 as a Peruvian port and annexed by Colombia in 1922 after a war with Peru, Leticia has been governed by a frontier spirit that attracts adventurers, outlaws and smugglers.

Located more than 500 miles from the nearest Colombian highway, Leticia received most of its goods from the Amazon, which is more than a mile wide as it flows by the town. The few vehicles in Leticia - primarily motorcycles and battered Volkswagens from Brazil - were shipped in by barge.

"It's very expensive to live here," said Mayor Dosantos as he paced his air-conditioned office on Leticia's palm-shrouded central square.

Leticia is a small city - primitive in comparision to the rest of Colombia - but by far the fanciest town for hundreds of miles along the Amazon. The commercial center is 10 blocks square.

Most of the town's structures are constructed of rough-hewn lumber and tin roofs. To avoid frequent flooding, buildings near the river are elevated on stilts.

Indians arrive by boat to sell fish and fruit, their plastic sheets spread in the town market on the banks of the Amazon. Dozens of buzzards peck at garbage, strewn over the river bank, as it cooks into a pungent stew under the scorching tropical sun.

The river has always been central to Leticia's trade in contraband.

Military officials say the port was one of the main entry points for smuggled arms during La Violencia, Colombia's great political war of the 1940s and 1950s.

Signs at Leticia's one-story airport warn travelers not to buy skins of tropical animals such as jaguars and monkeys. And Colombian customs officials search luggage on all domestic flights through Leticia for untaxed goods from Brazil and Peru.

A region accustomed to open borders was perfectly matched to the Colombian cocaine cartels, which buy coca paste produced in Peru and Bolivia and smuggle it into clandestine laboratories in Colombia to be refined into cocaine.

According to Dosantos, the airstrips around Leticia were used primarily to refuel airplanes before they continued to laboratories deeper inside Colombia.

But several residents in Puerto Narino, an Indian settlement on the Amazon about 60 miles from Leticia, recalled when giant cocaine-processing complexes operated in the jungle.

Residents called one airstrip near Puerto Narino the "International Airport" because it was so busy with air traffic.

"Planes would come in from Peru and Bolivia and would leave for the United States," said a town official in Puerto Narino.

The cocaine laboratories altered the lives of the Ticuna and Yagua Indians in the region, according to a Colombian researcher who is studying the tribes. Indians were employed to haul chemicals or goods to the laboratories by stream. But the chemicals discharged by the laboratories also wiped out the fish in several streams.

"There was a time here when the dollar was more common than pesos," said the Puerto Narino town official. "The economy was a lot better when they were operating here."

The traffickers also exerted their financial influence in Leticia. The local hospital was expanded with the assistance of donations from people hospital officials described simply as "Medellin businessmen."

The drug traffickers also exerted their power ruthlessly. A former policeman, who now operates a boat service on the Amazon River, said he quit the police force four years ago after too many of his colleagues died at the hands of the traffickers.

"The mafia was too much for me," he said.

Three years ago, the Leticia correspondent for the newspaper El Espectador was shot to death after the newspaper reported on the military operations to clean out the traffickers.

By all accounts in Leticia, the Colombian military broke the cartel's grip on the town about four years ago with a series of attacks aimed at the jungle laboratories.

The three men identified by the military as the leading local drug traffickers - Vicente Rivera Gonzalez, Francisco Barbosa Estupinan and Alberto Villarreal Diago - have not been seen in Leticia since the military offensive. But as evidence of the traffickers' lasting power, most residents in Leticia still are afraid to say anything against them.

And the government's crackdown during the last month demonstrated that the military had not eradicated cocaine trafficking from the region.

In addition to the confiscations of 12 houses and five ranches in Leticia, Gen. Rodriguez said the military had seized 200 acres of fields planted with coca shrubs, four cocaine laboratories, 13,200 pounds of coca paste and 14 tons of chemicals used to process coca leaves into cocaine.

And there are rumors that some leaders of the Medellin cartel have been hiding out at nearby encampments in the jungle.

"When there are problems in Colombia, they just go across the border into Brazil or Peru and the authorities can't reach them," said a teacher at the town's whitewashed schoolhouse.

To Rodriguez, the army commander, such a situation is not out of the question.

"It's very possible," he said. "But so what?