SPRUCE HEAD — A 31-year-old Rockland man has been charged with making a false distress call late last year that resulted in a large search effort and drew condemnation from the Coast Guard for coming shortly after a fishing boat out of Portland was lost at sea claiming the lives of four fishermen.

A criminal complaint filed Wednesday in U.S. District Court in Portland charges Nathan Libby with communicating a false distress call on Dec. 3. He is scheduled to make his initial appearance in U.S. District Court in Portland on Monday. Libby faces up to five years in prison and a $250,000 fine if convicted of the crime.

Court documents don’t list a lawyer for Libby, who was being held at Cumberland County Jail on Friday night.

The Coast Guard sent out a vessel that searched for more than four hours and a helicopter from Coast Guard Air Station Cape Cod spent more than five hours in the search on Dec. 3. The Maine Marine Patrol and private boats also helped in the search.

The hoax call came less than two weeks after the Coast Guard mounted an extensive search for four fisherman who were aboard the Portland-based Emmy Rose when it sank off Cape Cod on Nov. 23. The search turned up debris and an empty life raft but the fishermen were never found.

A Coast Guard official condemned the hoax call at the time.

“Today’s hoax is particularly offensive given the loss of four fishermen aboard the Emmy Rose just last week,” Capt. Brian LeFebvre, commanding officer of Coast Guard Sector Northern New England, said in a statement on Dec. 3. “We will use all available resources to identify and hold the responsible individual accountable.”

The charge against Libby is outlined in an affidavit filed in court by Coast Guard Investigative Service Special Agent Mark Root.

The Coast Guard received a mayday call shortly after 6:30 a.m. on Dec. 3 on VHF marine radio Channel 16. The Coast Guard dispatcher spoke with a man for about one to two minutes during which time he said he was on a boat that had lost its rudder and was taking on water fast and the pumps couldn’t keep up.

“Mayday, mayday, mayday,” says the voice in an audio recording released by the Coast Guard Sector Northern New England. “We lost our rudder and we’re taking on water fast. I just don’t have enough pumps to keep up with it.”

The man said there were three people aboard the boat and they were in Spruce Head Harbor and trying to get to the Atwood float.

Marine Patrol Officer Nicholas Stillwell responded to Atwood Lobster Co.’s wharf on Spruce Head Island in South Thomaston and boarded a private vessel in an attempt to locate the boat that made the distress call. No vessel was located.

Stillwell returned to the dock and spoke to Libby, a dock worker at the neighboring Spruce Head Fisherman’s Co-op. Libby provided Stillwell with a list of boats that had gone out that morning.

The officer then spoke to someone else at the co-op and played the recording of the distress call. That person said the voice sounded like Libby. The officer went back and spoke to Libby, who said he had heard the distress call. He also acknowledged the co-op office had a VHF radio that was on Channel 16.

The officer taped Libby and his voice was compared to the distress call by an associate research professor at the Language Technologies Institute School of Computer Science at Carnegie Mellon University in Pittsburgh. Associate Professor Rita Singh concluded the voice on the distress call was the same as Libby’s, the affidavit states.

Surveillance video showed that Libby was at the co-op office at the time the distress call was made. And a check from a radio tower showed the call came from the direction of the co-op.

The Coast Guard said that Libby is not a suspect “at this time” in another fake distress call that went out in October 2019. In that case, which kicked off a 22-hour search, the purported “emergency” involved a man and three children and a capsized boat off Kennebunkport.

Coast Guard officials say that fake distress calls tie up resources that may be needed for a vessels that are actually in trouble.

“Our Coast Guard rescue crews thrive on taking risks for the sake of helping others in distress on the water,” LeFebvre, the commanding officer of Coast Guard Sector Northern New England, said in the wake of the fake call on Dec. 3. “Hoax distress calls – like the one we received this morning – unnecessarily put our rescue crews at risk, drain resources, and may limit our ability to respond to actual emergencies.”

Press Herald Staff Writer Ed Murphy contributed to this report.