Two groups of Cubans -- including 16 who had been stranded on a muddy flat and had to be lifted out one-by-one into a U.S. Coast Guard helicopter using its basket seat -- arrived on Big Pine Key within a 12-hour period that ended early Tuesday morning.

Totaling 43, they are part of a growing attempt to smuggle Cubans to the United States, said Dan Geoghegan, assistant chief of the U.S. Border Patrol office in Miami.

One man, part of the group that arrived just after daybreak Tuesday in what's dubbed Big Pine's ``swimming hole,'' told a Florida Marine Patrol officer he paid ``five thousand pesos'' for the two-day, two-night voyage.

The man did not specify whether his reference to pesos was to Cuban pesos or U.S. dollars, FMP Officer Vicente Lopez said. It makes a big difference: 5,000 Cuban pesos equals about $250. Smugglers have been charging thousands of U.S. dollars to bring Cubans to this country.

Two other Cuban men were found early Tuesday on Key Biscayne, but Border Patrol agents believe their arrival was staged. They were found at 3:30 a.m. at Miami Marine Stadium, wearing clothes that appeared to have been bought here. Both men were also cleanshaven and well rested, Border Patrol officers said.

The landings bring the number of Cubans who have reached South Florida this year at 458.

The Border Patrol's fiscal-year count shows the enormous growth in the numbers of Cubans arriving, whether smuggled or on their own:

During the Patrol's fiscal year 1998, which ended last October, 615 Cubans reached South Florida by sea. Now, just six months into the current fiscal year, 848 have already made it.

The Lower Keys landings began at 8:30 p.m. Monday, when the Florida Marine Patrol spotted a group stranded on the mud flats off of Big Pine's Long Beach Road. The area isn't accessible by car, and was too shallow to reach by FMP boat.

Three Cubans had already waded to shore, but 16 were stuck on the flats. The group included nine men, five women and four children, Geoghegan said.

A Coast Guard helicopter arrived and picked up two, but had to return to base to refuel. A second Guard helicopter picked up the rest.

Monroe County Sheriff's Office Sgt. Daryl Hull, a member of the department's dive team, put on wet suit and waded out to the refugees to assure them they'd be safe, said Deputy Becky Herrin, Sheriff's Office spokeswoman.

``He stayed with them all night,'' Herrin said. ``It was not pleasant at all. The mud, you can hardly wade through it, and it was cold, too.''

A bus from the Krome detention center in South Miami-Dade County was taking them there when it was detoured to pick up the other group: the 23 adults and two kids who had been found at the swimming hole on Big Pine's southern tip.

The Border Patrol is investigating whether the two landings are related. No boat was found in either case, though FMP received a call early Tuesday about a skiff apparently bringing groups of people to shore, FMP Officer Lopez said.

All 43 refugees were taken to the Border Patrol office in Pembroke Pines, where they were interviewed late Tuesday, before being taken to Krome, Geoghegan said.

Lopez, the Marine Patrol officer, was outraged at the price the refugees had to pay to get to the United States.

``It was sort of a heartbreaking thing, you know what I mean?'' he said. ``I'm a very naive person sometimes, but if I was going to run to Cuba to help the Cubans, and I'm a Hispanic, it would be to help those people because they are suffering. I would do it out of m y heart. My heart would bleed for them.

``These damn smugglers are no different than those dopers.''