The men had jumped into the water near the Legoland theme park to rescue Ortiz’s girlfriend, 38-year-old Velcky Velasquez, who had gone into the water to set the anchor.

Grady said the group were "novices" and "passed a basic test to rent the boat."

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"She's just very inexperienced, so she thinks that you have to get into the water, put the anchor in and then tie it to the boat," Polk County Sheriff Grady Judd said Sunday.

As Velasquez was in the water, officials said the boat began to float away, and the two men jumped in to help her. 

Judd described the lake conditions as rough with 20 mph winds and some whitecaps. He said the men were not strong swimmers and wound up going underwater.

Using sonar equipment and an underwater drone, officials found their bodies 300 to 400 yards offshore and about 16 feet beneath the lake’s surface, Judd said, adding that dive teams recovered both bodies.

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While the men are presumed to have drowned, the medical examiner will conduct autopsies to determine their exact causes of death. 

Ortiz and Velasquez had rented a 16-foot Tahoe ski boat to celebrate their one-year anniversary with Marrero and his two daughters, ages 10 and 8, the sheriff’s office said. The 10-year-old girl had called 911 when the adults were in the water.

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The children were both wearing life jackets, and other life jackets were found in the boat, Judd said Monday.

"The only question that we have is why wasn’t the tow rope already tied to the boat," Judd said.