MIAMI, Florida (CNN) -- The FBI is searching for the four-person crew of a Miami Beach charter boat as part of an investigation into what a bureau spokeswoman called "a possible crime on the seas."
Capt. Jake Branam and three crew members of the Joe Cool are missing, the FBI says.
Relatives of the crew of the 47-foot charter fishing boat Joe Cool called authorities Sunday evening to say the vessel had not returned as scheduled after being hired Saturday afternoon.
Late Sunday, the U.S. Coast Guard spotted the boat floating 160 miles south of Bimini with no one on board, its contents in disarray and one life raft aboard.
"It looks like whoever was on board left in a hurry," Coast Guard Petty Officer James Judge said.
Missing are the boat's captain, Jake Branam; his wife, Kelly; and crew members Scott Campbell and Sammy Cary.
A Coast Guard helicopter spotted the boat's second life raft, containing the two men who had chartered it, about 12 miles north of the empty boat and took them to a Coast Guard cutter, where the FBI questioned them. Watch Branam's cousin describe how the two men chartered the boat »
The men have been identified as Kirby Archer and Guillermo Zarabozo. Police said that the men chartered the boat from the Miami Beach Marina for what was described as a planned trip to Bimini.
"We're investigating this as a possible crime on the seas," FBI spokeswoman Judy Orihuela said.
Police would not say what, if anything, the two rescued men have said.
Investigators are checking to see whether Archer is a 35-year-old fugitive with the same name who has been missing since January, when he allegedly stole more than $92,000 in cash from a Wal-Mart in Batesville, Arkansas.
"We want to go on more than a photograph," Orihuela said.
Independence County, Arkansas, Sheriff Keith Bowers said that the man wanted in his state is a manager responsible for collecting cash from store registers who allegedly hid some money in a microwave box and then walked out of the store.
"That was the last anyone's seen of him," Bowers said.
The second man being questioned is Zarabozo, a 19-year-old from Hialeah.
Miami TV station WPLG reported the men paid for the charter with $4,000 in $20 bills, saying they were construction surveyors.
"I don't think the crew ever made it to Bimini. I think the boat did. I don't think they did," the captain's uncle, Jeff Branam, told WPLG. "I'd like to think they dropped them off somewhere, but I don't know." E-mail to a friend
CNN's Cristy Lenz contributed to this report.
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