Updated

Police said Saturday that three men have become "the most important lead" in the case of the Alabama teenager who disappeared in Aruba — and vowed that "there will be developments" in the next few days.

Deputy police chief Gerold Dompig said authorities were investigating the background and story of two Surinamese men and a native of the Netherlands who said they dropped off Natalee Holloway (search), 18, at the Holiday Inn before dawn Monday.

Dompig declined to call the men suspects, saying they were "persons of interest," but said the men were "the most important lead."

"We are working diligently," Domping said. "I want everybody to hold their breaths for the next 24 hours. There will be developments after this weekend."

Police, Dutch troops and hundreds of volunteers scouring coastline and beaches for six days have found no trace of Holloway.

The focus of Saturday's search was on a closed hotel near the Holiday Inn where Holloway had been staying. Officials said they received a tip to search the Allegro Hotel, which is currently closed for renovations. The hotel's casino, however, is still open.

The three men who have emerged as persons of interest are legal Aruban residents between the ages of 18 and 25. They told police they had taken Holloway to a beach at the northwestern tip of Aruba before dropping her off at the hotel, according to an official close to the probe.

But her uncle, Paul Reynolds, said he was told security cameras did not show Holloway returning to the hotel that night. Police declined to comment on that report.

Holloway was on a five-day excursion with 124 seniors and several chaperones from Mountain Brook High School, near Birmingham, Ala. She spent the last night of her vacation eating and dancing at Carlos 'N Charlie's bar (search) and restaurant.

She didn't show up for her return flight, and police found her passport in her hotel room with her packed bags.

"Natalee's bags were packed and she's ready to go home," her mother, Beth Holloway Twitty, told a news conference. "Please help bring her home."

Holloway, a straight-A student, had earned a full scholarship at the University of Alabama (search) and planned to study premed, Reynolds said. He described his niece as a levelheaded girl who would not have done anything rash.

Ten more FBI agents joined the search Saturday for the girl, Attorney General Caren Janssen said. "We need more technical assistance," she said, declining to elaborate.

Aruban Prime Minister Nelson Oduber said Holloway's disappearance has dismayed an island that prides itself on its safety and friendliness — a haven for the 500,000 American visitors last year.

"Learning the news of Natalee's disappearance on our island left us all in a state of shock and disbelief," Oduber said. "We will not tolerate any activities that harm our American friends or tarnishes Aruba's reputation."

A $50,000 reward has been offered for information leading to Holloway's rescue, said Myrna Jansen (search), the director of Aruba's tourism office. The Aruban government and local tourism organizations were contributing $20,000, while family and benefactors in Alabama were offering the rest, she said.

Aruba's coast guard began searching surrounding waters, indicating authorities were considering the possibility Holloway was taken off the island with or without her consent. Police found her passport in her hotel.

Police receive tips every hour, but "none has proven to be the golden tip," Janssen said.

The search has not been extended to Venezuela, whose coastline is only 25 miles from Aruba at the nearest point, or the neighboring Dutch island of Curacao, van der Straaten said.

Holloway earned a full scholarship to the University of Alabama, where she planned to study premed, said her uncle Paul Reynolds, who traveled from Houston to help in the search.

Reynolds said his niece was a responsible person who would not have run away.

"Natalee is very smart and focused," Reynolds said. "It never crossed my mind that she intentionally missed the flight. When she did, I knew something was terribly wrong."

Posters with a photograph of Holloway have been put up throughout island, with a caption reading: "Kidnapped since 1:30 a.m. May 30."

On an island remarkable for its friendliness, pristine beaches and an absence of violent crime, Holloway's disappearance has shocked islanders, many of whom say they are optimistic she will be found alive.

"She's not on the island," said Jany Winterdal, a 51-year-old taxi driver. "In Aruba, we don't know what doing bad things to people is. For me, she's alive."

There have been two murders and three rapes on the island of 72,000 people this year, compared with one murder and six rapes last year, none involving foreigners, police said.

Aruba has an average of 13,000 tourists a day at this time of the year, the Tourism Authority said.

FOX News' Mai Martinez and the Associated Press contributed to this report.