Uncle, 57, and Nephew, 33, Missing After Disappearing on a Fishing Trip, Family Says They’re ‘Heartbroken’ as Search Continues

Randall Spivey, 57, and Brandon Billmaier, 33, were last seen near Fort Myers, Florida, on Friday, Dec. 19

Authorities in Florida are asking for the public’s assistance in locating two missing men.

On Saturday, Dec. 20, the Lee County Sheriff’s Office (LCSO) launched an urgent search for Randall Spivey and Brandon Billmaier following the “endangered adults” disappearance the day before.

“The two left early yesterday morning for a fishing trip on a 42FT Freeman boat from a residence on the 15000 block of Intracoastal Ct in Fort Myers,” the LCSO wrote on Facebook.

Spivey, 57, is a white male with brown hair and brown eyes. He is 6 feet 1 inches, weighs 245 pounds and was last seen wearing khaki pants and a dark-colored shirt, according to the post.

Billmaier, 33, is described as a white male with strawberry hair and brown eyes. He is 6 feet 2 inches and weighs 250 pounds.

Capt. Corrie Sergent, Sector St. Petersburg commanding officer of the U.S. Coast Guard, said in a statement to PEOPLE on Sunday, “Today, we continue to search with air and surface crews, pursuing all leads and saturating the search area. Thank you to this amazing community for their support. Our thoughts are with the families as we continue our efforts.”

The U.S. Coast Guard added to PEOPLE that the organization is “working day and night with the goal of locating the missing boaters and returning them home to their loved ones.”

Billmaier’s wife, Deborah, shared an Instagram post revealing there is a monetary reward for finding the uncle and nephew.

“I am heartbroken posting this. My husband, Brandon, went out fishing yesterday with his uncle off the coast of Fort Myers,” she wrote in the caption of the post. “They left early in the morning on Friday, Dec. 19 and were meant to come back that afternoon.”

“At 7:30, we had not heard back from them, and we contacted the U.S. Coast Guard. At approximately 11 p.m., they deployed a helicopter,” she continued.

Deborah said that at 1:30 a.m. local time on Sunday, Dec. 20, she “received a call that they had found the boat (70 miles off the coast) but no one was there.” She added, “The helicopter has continued searching throughout the night. As the sun rises, we are looking for additional help in the search efforts.”

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Billmaier is a personal injury attorney and the founder and president of Spivey Law Firm, according to the company’s website.

The U.S. Coast Guard St. Petersburg announced in a Facebook post on Saturday that a search is taking place in the area where the two men were last suspected to be.

“Search and Rescue operations are being conducted from the surface up to 5,000 ft. approx. 35 statute miles around position 25-36N 083-16W,” said the U.S. Coast Guard. “All aircraft are advised to maintain situational awareness and not interfere with search and rescue crew.”

The Coast Guard warned that uncoordinated crews operating in the search area may delay response efforts and create unsafe conditions in the area.

PEOPLE has reached out to the LCSO for further comment.